# vr6 turbo runnig rich @ idle, lean under boost (and power loss) c2 obd1 36lb - HELP!



## Corsten (Sep 26, 2005)

Hi guys I just finished my turbo project. Here is the info:

1994 corrado vr6, 4.0 bar fpr,
changed MAF from 5pin to 4 pin (rewired as per thread here on vortex) in order to use obd1 ECU EA/BM

using c2 motorsports obd1 36lb software v30 with EA ECU

the car is running extremely rich (10.0 afr) it actually might run below that because the reading flashes - removed spark plug to confirm - super black.

I tried to make a soft run, and when the boost is starting to creep up (part throttle) AFR jumps to 20 (and flashes again so I guess it goes out of range) and the motor experiences total power loss (as if you would cut off fuel supply). did not try to go half or WOT not to damage the engine.

I scanned the engine for codes at idle - nothing, after the drive:

*00525 - Oxygen (Lambda) Sensor (G39): No Signal*

now, could this be because of the missing (by factory in obd1 cars) post-cat o2? , 
how would I know if it refers to the o2 before the cat or after?. also I do not have a cat.
o2 was proactively replaced about 2 years ago.

Will try to hook up a different obd2 ECU (non c2) to rule out software flaw.

Do you guys have any ideas?, 
would a 4bar FPR be at cause here?, as far as i can remember obd2 software was written for 3.0 bar FPR because that's what the original obd2 mk3 vr6's are running


----------



## SVTDanny (Aug 8, 2005)

Sounds like you're having worse problems than a wrong FPR would cause, but yes, you do need a 3 BAR.


----------



## SpOoOling1.8T (Dec 12, 2004)

check for vaccume leak


----------



## vergessen wir es (May 12, 2010)

021 906 258 ea is from a 1995 OBD1 car.
4 bar FPR=OBD1
Solder in chip = OBD1
Not to confuse things but i think they also called this OBD1.5. Either way from the above you are not OBD2 unless I am missing something.

If you are C2 then post O2 is ignored as is egr and SAI afaik.


----------



## Corsten (Sep 26, 2005)

right, makes sense, what was I thinking? 

so it is 1.5obd1 or whatever you want to call it.

So does it mean that I should not change my FPR?, I'm running super rich at idle. Today I started the car which was backed up all the way against the garage closet and after I moved it out of (after the car was running for a while) there was a huge black stain on it. It also backfires and there's a black smoke coming out of the exhaust when I rev it hard.

OK, so I test drove the car. IT seemed OK, was so much fun to drive (only with a red spring so I guess 5psi?) that I was unable to have all gauges under my control. Anyway, fpr seems to be between 10 and 12 when driving normally, can't remember what it was at WOT., but the car is running fine, don't know why. I filled up the gas tank with fresh gas.

I will be putting an MBC soon, question is, should I leave it like that? should I change my FPR? is everything OK? what about the O2 sensor error code?

I cleared errors, and after I test drove it today the O2 00525 error appered again. Is this normal?:what:


----------



## vergessen wir es (May 12, 2010)

G39 is pre cat and needs to be working. Check your wiring. You should stay 4 bar FPR per OBD1. Do you have the 4" MAF housing? Maybe check your CTS. If faulty can run rich. Your AFR at idle should be around 14.7. For example, I have the same chip and my AFR is 14.3 to 15 out of boost. I richen up steadily with boost until I am low 11s at 15 psi; high 10s above 15 psi. ( so I keep it at 15 psi for now). Is your MAF new-ish?


----------



## Corsten (Sep 26, 2005)

I can't remember it showing the exact number for the o2 sensor, will use another version of vag com that one might have been a bit old. *[EDIT: it is G39 I even post it up above]*
How do I know if my O2 is working? When I connect VAGCOM I the value for O2 is 1
I only get this error when in boodt I guess, why wouldn't this show at idle?

now, MAF is 4" no idea how old it is, I received it with the setup. Might give new one a try, this has has been cleaned thoroughly before I fitted it in.
*[EDIT" when I unplug MAF the car is about to die so I guess it works fine]*

What's CTS? did you mean crankshaft possition sensor? if so I replaced it last year.
*[EDIT: OK, you meant coolant temp sensor]*

and as for 5psi,. I thought it would be much faster....


----------



## SVTDanny (Aug 8, 2005)

Coolant temperature sensor. The blue one on the thermostat housing.


----------



## Corsten (Sep 26, 2005)

djsheijkdfj said:


> Coolant temperature sensor. The blue one on the thermostat housing.


Why would I think it's a blue temperature sensor when I connect VAGCOM and I can see the temp reading being OK? - it that the sender that vagcom takes the readout from?


----------



## Corsten (Sep 26, 2005)

so I checked my blue coolat sensor today, the ohm reading changes along with temperature. it shows 230ohms at operating temperature. So I read somewhere people posting having around 180ohms or so. Well mine seems just fine then

actually I don't get people exchanging electronic things on their cars without testing, just because people tell them to.... :screwy:











how do I check my lambda? (o2) what should the reading be in vagcom? I'm getting a value of 1


----------



## vergessen wir es (May 12, 2010)

Lean in boost could be spark related, though you are at low boost, but still worth checking. Which plug and which gap? Should be Bkr7e at no more than .028". Most have best luck between .022" and .028". I run .022". Autozone PN 4644


----------



## Corsten (Sep 26, 2005)

I'm running Bkr7e at 0.022"-0.024"


----------



## Corsten (Sep 26, 2005)

I checked the car with O2 unplugged, no change. Same AFR. What do you guys guys when you disconnect O2 sensor? how does the ECU react to it, can you please check and let me know?


----------



## Corsten (Sep 26, 2005)

guys, anyone?


----------



## vergessen wir es (May 12, 2010)

Without O2 you might be stuck in warmup enrichment, which for me is between 10 and 12 AFR. Gotta verify O2 operation. Lean in boost may just be a separate issue, since O2 isn't in the calculation.


----------



## Corsten (Sep 26, 2005)

I can always count on you brother  thanks for helping!
I'm running 12.5 in boost, so I guess it's OK? or still too rich? (I'm only at 5psi now) when I sort everything out will turn up the boost.
hmm....so you're getting between 10 and 12 with O2 disconnected?, strange, I get between 10 and 11 but it usually is flashing 10, meaning even richer (out of scale)


----------



## vergessen wir es (May 12, 2010)

12.5 is pretty ideal for that boost level. And when you go higher I am sure you will keep an eye on it. I'll double check, but it starts out pegged rich then pretty quickly is in the 10s then slowly works its way up to 12s then it kind of speeds up and finds stoich.


----------



## Corsten (Sep 26, 2005)

a little update. 

I've managed to find and fix the issue with rich idle. It was a damaged (cracked) wire (which was previously soldered by someone) going from one of the leads of oxygen sensor to the ECU pin # 20.

I checked out all leads as per wiring diagram of o2 and they all check out, beside one, the one that is supposed to go to the oxygen sensor relay, I've never heard about having one??? need to double check, didn't find it in the bentley?

Anyway, the car still runs like crap part throttle. WOT is fine - pulls great, part throttle it's a hake cap.
When I step on gas part throttle or half throttle, it hesitates a bit then slowly revs up (I see a needle on boost gauge going to 0) then AFRs show 20 (super lean - as if I let go off throttle, but I'm not) and the car decelerates until I blip throttle.

Could it be a fauly TPS? how do I check it? I already replaced crank position sensor last year.
Can't scan it for codes now, my laptop broke :banghead::banghead::banghead: but I wasn't getting any before aside for the mentioned o2 sensor.


Also I've noticed that when the car was running at idle - first start after fixing o2) AFR's are around 14-15 and suddenly go to 12... I need to check that sensor regardless, I think the car was running better with it disconnected.


----------



## vergessen wir es (May 12, 2010)

Yeah sounds like a bad tps And/or bad maf. You can scope a tps and you can try with a meter but unless it is really really bad it will be hard to determine condition. If the tps is original replace it, it is a film resistor with wiper contact and just doesn't last forever. They are cheap. Many will argue but imo any sensor from a 94 is going to be suspect. And that goes double for OBD1 because we and any previous owners did not have adequate diagnostics in the ecu to detect them. At one time or another I have had a bad maf, tps, cps, and ess all without getting codes.

Oh, and on my OBD1 95 there is an extra black wire left unconnected at the harness side of the O2 connector (harness has 5 wires---O2 has 4). This is normal from the factory. Just letting you know in case that is a question.


----------



## Corsten (Sep 26, 2005)

my TPS checks out OK








[


----------



## a2vrtboosted (Jun 19, 2011)

i feel your pain.... check my thread


----------



## magner (Jul 26, 2009)

try resetting the ecu disconnect the battery turn ignition on short battery leads together for a while to discharge the ecu. turn ignition back off and reconnect the battery


----------



## Corsten (Sep 26, 2005)

The ECU was reset multiple times already.... I've done some preliminary tests for MAF, seems to be fine as well.... I guess I'm a bit stuck now....

It there a way for OBD1 to do throttle adjustment or setup, alignment?


----------



## a2vrtboosted (Jun 19, 2011)

Corsten said:


> The ECU was reset multiple times already.... I've done some preliminary tests for MAF, seems to be fine as well.... I guess I'm a bit stuck now....
> 
> It there a way for OBD1 to do throttle adjustment or setup, alignment?


no there is no way.... i have a feeling it is OBDI issues


----------



## GinsterMan98 (May 19, 2008)

You need a flow corrector, you are more than likely getting turbulant air through the MAF causing irradic fueling. I just picked up one from www.saxtonpc.com.
Only happens at partial load, right?


----------



## Boost112 (May 8, 2002)

GinsterMan98 said:


> You need a flow corrector, you are more than likely getting turbulant air through the MAF causing irradic fueling. I just picked up one from www.saxtonpc.com.
> Only happens at partial load, right?


...i was looking at the same exact thing... which ratio did you pick up and was it plastic or aluminum?


----------



## GinsterMan98 (May 19, 2008)

Aluminum 5:1 ratio, it was like 10 bucks or something. Chevy and Mustang guys seem to swear by it. They all run MAF based tunes.


----------



## optiks (Mar 15, 2003)

what maf do you have ginster man, i have the exact problem you describe on my c2 ob2 630cc promaf file


----------



## GinsterMan98 (May 19, 2008)

optiks said:


> what maf do you have ginster man, i have the exact problem you describe on my c2 ob2 630cc promaf file


You are running a Pro MAF and still have problems? I have a OEM maf in mine, OBD2 42# stuff.


----------



## SVTDanny (Aug 8, 2005)

Did you get the 103.5 or the 100 for the 4" MAF?


----------



## Boost112 (May 8, 2002)

djsheijkdfj said:


> Did you get the 103.5 or the 100 for the 4" MAF?


4" housing is ~ 95mm


----------



## GinsterMan98 (May 19, 2008)

djsheijkdfj said:


> Did you get the 103.5 or the 100 for the 4" MAF?


100mm, my maf housing is home made and is slightly smaller than the commercial versions out there.


----------



## GinsterMan98 (May 19, 2008)

You know since it was brought up, you can run a promaf on any tune. You can just get it calibrated for your injector size.


----------



## Corsten (Sep 26, 2005)

GinsterMan98 said:


> You need a flow corrector, you are more than likely getting turbulant air through the MAF causing irradic fueling. I just picked up one from www.saxtonpc.com.
> Only happens at partial load, right?


Hey, this was my thought exactly today after I came across somebody else's post about it. I didn't replace anything yet, but when I performed measurements my TPS checked out along with my MAF, I might replace them eventually but I will try the honeycomb thingy first. should I get only one? or two? (before and after MAF)?. 
And it does happen only at part throttle, around 3500rpms is the worst (as if the fuel got cut off - 20 on AFR gauge) where some boost is concerned.

I also got this code:
VAG-COM Version: Release 311.2-N

Control Module Part Number: 021 906 258 C2 
Component and/or Version: C2 v30k 607 1
Software Coding: 0261203223
Work Shop Code: 1267358467
1 Fault Found:
00537 - Lambda (Oxygen Sensor) Regulation
11-10 - Control Limit Not Reached - Intermittent

will have a look at my lambda, it's pressed against upper tunnel after installing kinetic downpipe, I hope the wires are not damaged. Will check thtat. But if the lambda checks out then I guess it's mixture related - could be the turbulence in the MAF. What did it do for you once you installed it?


----------



## Corsten (Sep 26, 2005)

just checked rosswiki

*Possible Symptoms *
Lambda Control inactive 
Engine running rough 
*Possible Causes *
Activated Charcoal Filter Solenoid Valve 1 (N80) leaking/sticking 
Injector faulty (not closing completely) 
Fuel Pressure Regulator faulty 
*Possible Solutions *
Check/Replace Activated Charcoal Filter Solenoid Valve 1 (N80) 
Check/Replace/Clean Injector(s) 
Check Fuel Pressure Regulator 

Retrieved from "http://wiki.ross-tech.com/wiki/index.php/00537"

I have my evap deleted, solenoid is connected but the inlets are open, should I block them somehow?


----------



## GinsterMan98 (May 19, 2008)

Corsten said:


> just checked rosswiki
> 
> *Possible Symptoms *
> Lambda Control inactive
> ...


Evap should be good then, just has to be plugged in to keep the ecu happy.
I have not installed my maf thingy yet, but it will be in front of it.


----------



## GinsterMan98 (May 19, 2008)

Corsten said:


> Hey, this was my thought exactly today after I came across somebody else's post about it. I didn't replace anything yet, but when I performed measurements my TPS checked out along with my MAF, I might replace them eventually but I will try the honeycomb thingy first. should I get only one? or two? (before and after MAF)?.
> And it does happen only at part throttle, around 3500rpms is the worst (as if the fuel got cut off - 20 on AFR gauge) where some boost is concerned.
> 
> I also got this code:
> ...


Yes, on my car it was the worst putting around at about 3k. It would also do it on the highway. Mine cleared up with any large throttle application, WOT was mint. I say was because that car is gone, my new setup UM 42# chip is much better. It still stumbles a tiny bit from time to time, not even noticeable really. You should try and move the filter off the maf and get it as far away as possible.


----------



## optiks (Mar 15, 2003)

GinsterMan98 said:


> You are running a Pro MAF and still have problems? I have a OEM maf in mine, OBD2 42# stuff.


 it could easily be a different issue. 

but the main issue im having with the car is stumbles at a cruise with minimal throttle


----------



## GinsterMan98 (May 19, 2008)

optiks said:


> it could easily be a different issue.
> 
> but the main issue im having with the car is stumbles at a cruise with minimal throttle


What is your O2 regulation look like short and long term. Promaf is way better than any oem setup, but depending on how your intake is setup it could have an effect on flow. Promaf says the maf has to be calibrated to the type intake you have. Are you running a short ram or a CAI setup? You are the first person I have heard of that is having cruise issues with the Promaf, kinda worries me because I was thinking about getting one instead of buying a new MAF the next time mine craps out. You might need to teek your accel and deccel trims in the adaptation block in vagcom.


----------



## Corsten (Sep 26, 2005)

not much time to work on the car, 
what I noticed is that car runs much better with O2 unplugged????? While it's in a rich loop it runs a LOT smoother. I still get the surge around 3500rpm though, so I guess I'm encountering two separate issues here.
I though I will post pictures of how I have my vacuum lines connected,.

now, if I got a boost leak, wouldn't I see a pressure drop on the gauge?


----------



## Corsten (Sep 26, 2005)

did some more observations:

Normal driving, without 02 - super rich, but very steady. 
with it connected, it behaves weird. It's worst when rpms are around 2K and lower. I hit gas pedal just a little (maybe like 15%) and I see AFRS climbing to 17, seems like the car is not accelerating, and slowly AFRs go down to 14, and it accelerates slowly. It usually happens all the time around this rpm. Also when I deccelerate in gear my AFRs are at 20 (super lean) until they go down to 2K, then car jerks slightly and I see AFR of 12. Do you guys get that too?????????

how are my vacuum lines connected? is my ISV OK? I hooked it up to the charge pipe exiting the intercooler, instead if a pipe going off of the turbo into the intercooler.


I'm posting a VAGCOM log at 3500rpms where I get the surge mentioned in earlier posts, can someone help?


----------



## SVTDanny (Aug 8, 2005)

Injectors shut off on decel, and click back on at 2,000 RPM. That's normal.


----------



## vergessen wir es (May 12, 2010)

(Injector cutoff) Like said above the injectors go to cutoff and the O2 sensor pegs lean. Iirc my gauge pegs off scale lean so just displays - - -. I'll verify that. The delay followed by a jerk is the throttle snapping closed after the dashpot strokes out and the isv takes over. Perfectly normal. Of course less delay if the dashpot is deleted.

ISV on mine is fed off the charge pipe right before the TB and feeds the stock port right after the TB. Pretty much just like yours.

(3500rpm surge) Like a surge in power? because your timing gets aggressive there as well. Maybe you can log a single very slow pull so you have steady increases instead of on and off throttle. Don't worry about getting into boost so much just the steady pull.

Not so important now but I read on here that it is better to run the dv reversed so that pressure is on the side port. That's for later with more boost tho.

For normal out of boost driving as i step on the gas the gauge goes pretty rich 11s and 12s for a second or two then normalizes at 14s for the rest of the acceleration. Just during launch really. I never go lean during driving unless I let off the throttle.

Boost leak test again and listen around the injector bosses. Depending what injectors you have they may not fit right in the manifold. I can't believe nobody else has had this issue but I was blown away that a kit would be like that. The injectors I received do not locate the same as stock. They can be too far into the lower intake or too far into the fuel rail, creating problems either way. I can imagine intermittent leaking of air or fuel there. I have a fix for that if you get into it. When I was planning my wastegate reroute I was concerned about air getting sucked into the DP using the spiral flex section. I can imaging a venturi effect pulling air right past the WB. I went totally sealed so there is no chance of it. I am sure I was just being overly cautious since not to many people do it.

You will probably have to replace the polyurethane hose with silicone at some point. PU doesn't like heat so much. I know not on topic.

Like we have discussed privately, the only time I have had throttle action that resulted in unexpected results it was TPS and or MAF. But I said that already.


----------



## 'dubber (Jun 15, 2004)

Did you know that your thread title says that you're OBD2 ? 


You should check out and post up in this thread, a lot of the same stuff going on in there.

http://forums.vwvortex.com/showthread.php?5337155-VRT-OBD1-OWNERS-Issues-and-fixes-Thread


----------



## Corsten (Sep 26, 2005)

oops, my mistake, I haven't realized it till now., will see if I could change it.

As far the link you mentioned, I subscribed....


Going back to the issue, I have ordered a new MAF, I don't think this is a MAF issue, but I guess I will need to start troubleshooting step by step. Also ordered a new TPS.

I'm doing a lot of thinking and here is where I am.
Since I am getting issues with weird car behavior in vacuum (around 2k) I'm thinking it might be caused by vacuum leak. But....as you can see in the pictures my vacuum lines are reduced to MINIMUM. I checked the capped brake booster nipple - seems fine. I will check all others - especially ISV ones. I believe I tightened them really tight. Could also be caused by a whole in a silicone coupler on the intake side? - is there any simple way to check for vacuum leaks?

I think I need to sort this problem first before I will try to sort the one with part throttle power surge at 3500rpm.

Oh, One more thing, I'm using bosh white top injectors, which a re shorter than the stock ones. I doubled the o-rings on them (manifold side), could this be the culprit? - when I think about taking it off to try other injectors (removing the whole front end who ch I have done like 5 times recently) just really makes me want to sell this car...:banghead:


----------



## vergessen wir es (May 12, 2010)

Good that you saw the injector thing. I found the distance between the orings on the white tops to be the same distance apart as stock, it's just that the injector body is much smaller so the body can't locate on the lower intake the way stock does. Also the white tops don't have the slot for the retainer clips like stock so really they aren't located the same at all.

I ran the extra oring in the fuel rail instead of the lower intake. I also put a washer around the injector at the lower intake. The washer prevents the injector from going to far into the lower intake and the extra oring in the fuel rail keep it all in place. 


Too far in fuel rail if you do nothing, which can cause vac/boost leaks at the oring boss.





OR too far into the lower intake. LOOK how the fuel rail side oring is more than half way out if the injector pushes into the lower intake. Yikes.




The extra oring in the fuel rail puts the injector right into stock position.




The washer around the injector body then keeps the injector located relative to the lower intake.



Your solution might be fine, but I don't remember how the oring would be retained in the lower intake, or whether there is still any chance to get out of position. The above way locates the injector positively with a little compliance from the extra oring. Just an alternative.


----------



## 'dubber (Jun 15, 2004)

Ok so you have an extra o ring at the fuel rail, but I can't see where you put the washer. Can you post more specific info on that, as well as part numbers in the other thread? How does your car run? Do you have any of the issues that we are describing in that thread? Also, I'm not sure if this probkem would explain why the drivability issues only occur once the engine warms up and fueling is dictated by the sensors or that it goes away when the o2 sensor is unplugged. I think that if the injectors were leaking vac/boost, it would be an ever-present issue.


----------



## Corsten (Sep 26, 2005)

Isn't that before the engine warms up (coolant at operating temp) ECU uses richer mixture? - well at leats I think that's why it's happening

It also worries me that someone in other thread described exact same symptoms as I am having with light throttle operation at 2000 rpm. I definitely need to try original ECU and software. Can I run it off boost and close to 0 boost on stock software??



> *Quote Originally Posted by marat_g60*
> ve run this tune in the past and overall was happy with it. In boost afr's were in the mid to high 11's, idle and cruising 14-15. However I experienced the same problem as you did around 2000rpm under light load it would bog down for a few seconds and afr's would read lean when this was happening. The only fix to that was unplugging the O2 sensor, but then it'd run richer overall. Other then that I had no other problems. Oh and I was using 38# Lucas( delphi) injectors from racetronix.


----------



## vergessen wir es (May 12, 2010)

'dubber said:


> Ok so you have an extra o ring at the fuel rail, but I can't see where you put the washer. Can you post more specific info on that, as well as part numbers in the other thread? How does your car run? Do you have any of the issues that we are describing in that thread? Also, I'm not sure if this probkem would explain why the drivability issues only occur once the engine warms up and fueling is dictated by the sensors or that it goes away when the o2 sensor is unplugged. I think that if the injectors were leaking vac/boost, it would be an ever-present issue.


The last photo is the best one I have of the washers. The washer goes around the injector body. If you look at the face of the injector boss on the lower intake you will see the washers. McMaster Carr PN 98089A392 http://www.mcmaster.com just put the PN in the find field.

I don't expect the injector issue has anything to do with their specific problem, just putting it out there. Leaks are possible without some action. Heat makes things move/get soft and going between vac and boost is pushing pulling on the injectors, plus valve events blah blah. The injectors need to be in a fixed position.

Car runs well and strong. WB says exactly what it should, when it should. I had a little stalling early on when clutching from over 3500 rpms (Jeffrey Atwood says this is normal ie don't clutch from high rpms), but even that has gone away. The only thing I did that maybe solved that is I fixed an exhaust leak and clipped pin 10--oh and went to 3" T-Back. I always had EGR and SAI deleted but always had the solenoids in. I swear the car ran a tad better after I clipped pin 10 even though I never had a cel and the solenoids were always in.

I need to post a video for these guys so they can see what it can be like so they don't get disheartened, just have to figure out how to mount the camera. Might do that today when it cools down cuz the windows should be closed for better sound.

I don't like the WG setup being on one side, which will make me go tubular divided at some point. I have no complaints except I am supposed to stay at 15 psi with OBD1. Others have pushed more and I have the pump for it, but the injectors are at 80% at 350 crank apparently, plus Jeffrey Atwood told me to keep it there so i am. Gonna Lug or MS it anyway.

I really question whether these guys have proper O2 regulation. Ie heater circuit etc, because my car definitely uses the stock O2 quite a bit.


----------



## vergessen wir es (May 12, 2010)

Corsten said:


> Isn't that before the engine warms up (coolant at operating temp) ECU uses richer mixture? - well at leats I think that's why it's happening
> 
> It also worries me that someone in other thread described exact same symptoms as I am having with light throttle operation at 2000 rpm. I definitely need to try original ECU and software. Can I run it off boost and close to 0 boost on stock software??


It will idle but you will have the wrong MAF diameter and wrong injectors so I have to believe you will get WB readings worse than what you have now if driven.


----------



## Corsten (Sep 26, 2005)

vergessen wir es said:


> It will idle but you will have the wrong MAF diameter and wrong injectors so I have to believe you will get WB readings worse than what you have now if driven.


Not sure about the readings, I do know the car will be drivable. I've already tried this set up before, 4" MAF and 30lb injectors on stock motor and software, it ran great (but rich since my 02 was not connected due to cracked wire). So I was thinking, to isolate the software issue I would revert back to stock software and see if anything changes, I'm just a little afraid when entering boost. However, I do recall reading somewhere people running 5psi of boost on stock software without any issues...


----------



## 'dubber (Jun 15, 2004)

I don't necessarily have to clutch in to get the problem to happen. I could go off throttle and coast in any gear, then when i reapply throttle it may respond ok or it may bog down and the afrs stay at 21 to 1, slowly recovering. My o2 is working and the trims are active. The heater is working. No egr or sai solenoids. I tried clipping the sai wire at the ecu but that gave me a cel so I hooked it back up. I have a spare isv that i want to take apart to see if something is clogged that cleaning does not clear. Also there is the epoxied set screw on it that I may try to mess with. My thing is that all of the original equipment was doing fine prior to kit install, which again points to software. I pressure tested for leaks and didn't detect any, and I paid close attention to the injector seals then. I have a 3" turbo back which did not affect the problem.


----------



## vergessen wir es (May 12, 2010)

Yeah could totally be software and nothing else, or damaged ecu or, or. Curious about your clipping sai wire?...this is not pin 10 right because I thought pin 10 is egr enable/disable. Anyway I definitely was getting the bog once in a while in the early days, and yeah I probably experienced it just coasting in gear, but only when coasting too long and letting the revs drop too low. I don't get it now, and I feel confident that is mostly from avoiding low revs. At the risk of being a broken record, I feel compelled to say...why would a vr be down at 2000 rpm, ever. There is just not that much going on for the 12v at that rpm. Or maybe my shiz bust, but don't think so.


----------



## Corsten (Sep 26, 2005)

I guess all of us are experiencing exactly the same thing with C2 OBD1 36lb software. Now, whether we notice it or not depends on the individual driving pattern.... I do get my rps low in gear and I do coast in gear, therefore I notice it a lot.... Don't ask me why I do that, I just drive this way...and always have been. Maybe a more now, since I drive a Turbo diesel daily..


----------



## magner (Jul 26, 2009)

pm me your postal address i will ship you this free


----------



## 'dubber (Jun 15, 2004)

The white wire at the ecu was either egr or sai, i dont remember, but cutting it resulted in a cel. Downshifting will put the engine to lower rpms between shifts, and I see the issue occur sometimes there. I'll blip the throttle to rev match and no response in terms of the engine revving up normally. Tps responds and maf sees the increase in airflow but the rpms dont jump with the blip. Afrs will be 21 to 1 on throttle. Ive tried a bunch of new plugs and gaps, might be at .023 now. Ill log some data but i need someone with excel to chart it.


----------



## Corsten (Sep 26, 2005)

GinsterMan98 said:


> You need a flow corrector, you are more than likely getting turbulant air through the MAF causing irradic fueling. I just picked up one from www.saxtonpc.com.
> Only happens at partial load, right?


this link ain't workin' no more...


----------



## SVTDanny (Aug 8, 2005)

http://www.saxonpc.com/

I'm going to purchase one of these for my 36# OBD1 setup. Having the same low RPM, partial throttle stumbling/hesitation that everyone else has. I have tested/swapped/replaced EVERYTHING that could be causing this - I pulled my hair out for weeks trying to find a solution before I found out that everyone else with the 36# OBD1 tune has the same problems.


It's a shame that C2 sells this ****ty tune with absolutely no mention of the issues that everyone has with it, and then when you email them about it, they never respond (Probably because they know they have issues with it but don't care, because they already got your money). :thumbdown: :thumbdown:


----------



## Corsten (Sep 26, 2005)

'dubber said:


> The white wire at the ecu was either egr or sai, i dont remember, but cutting it resulted in a cel. Downshifting will put the engine to lower rpms between shifts, and I see the issue occur sometimes there. I'll blip the throttle to rev match and no response in terms of the engine revving up normally. Tps responds and maf sees the increase in airflow but the rpms dont jump with the blip. Afrs will be 21 to 1 on throttle. Ive tried a bunch of new plugs and gaps, might be at .023 now. Ill log some data but i need someone with excel to chart it.


Hey, I read somewhere in your posts that you've put in that air straightener before and after MAF. Seemed like it solved issues for you and now I read this post. Does it mean it still runs the same way with or without the honeycomb air straightener?

no follow up here http://forums.vwvortex.com/showthread.php?5002986


----------



## 'dubber (Jun 15, 2004)

The straighteners did smooth things out a bit, my zietronix monitors maf voltage and the readout even looked smoother, but the problem eventually came back within a few miles. I think I edited or posted a followup in that thread.

I took some logs last night in vagcom/ vcds, if I email them to you, can you plot them in excel and post them ?


----------



## vergessen wir es (May 12, 2010)

So the problem is that under certain conditions the motor doesn't idle right and may stall if it can't recover, or doesn't respond right way when you get back on the gas, and may stumble, hesitate, jerk, lurch etc as it tries to get back on track. Basically the engine doesn't run right, but only under certain conditions.

I have been trying to reproduce it to try and understand it better and found out it is still there in my car and I can pretty much reproduce it at will (but can also avoid it 99% of the time). For my case it clearly has to do with injector cutoff and turn on or more importantly the transition from one to the other and back. If this is obvious I apologize. The injector cutoff and turn on threshold is at 2000 rpm more or less, but I think is also load dependent.

Anyway, It just so happens there is one off-ramp that tends to do it to me, which is always a surprise because it is like the only place it happens anymore. So what is special about this one ramp? Well, it is especially long, straight and slightly downhill. I always get off there after a long drive so I thought that was it but now I know it is the downgrade and length that is doing it. I see now that downgrades in general tweak out the injector cutoff and turn on code because the car's momentum can cause the car to go back and forth between being idle driven and engine braking. So on this particular off-ramp it is because it is long, and the light is always red, and there is always a cop so I coast longer than normal and with lower rpms so I don't draw attention with exhaust noise. Then I push in the clutch before the light and bang..stumble and maybe a stall.

Obviously this can happen on flat ground too when you go on and off throttle, which essentially is the same thing as cycling back and forth between engine braking and driving which deals with the same injector cutoff and turn on stuff. The key to avoiding it in how much LOAD the engine sees. The less vague the sensor inputs are and the more distinct the acceleration and coasting/engine braking modes are the easier it is for the ecu to figure things out. Want proof? Try making it happens on an incline. Bet you can't, because the acceleration load is very distinct and the decel or engine braking is also very distinct. Basically don't hang out in the 2000 rpm danger zone, where the engine doesn't know whether it's coming or going. Get back on the gas after coasting before the rpms drop below 2400 or so.

I totally understand people feeling this is an unacceptable weakness in the software, but hey if you want to double or triple horsepower the car may not have totally oem driveability. And frankly I think it has more to do with the combination of our ecus and lower resolution MAF setups due to larger MAF tubes, which is why I can believe that flow straighteners might help some. Obviously if you have other problems like O2s that are out of whack, or you are not making power, then you have more to complain about.

So one thing to try would be don't drive or coast near injector cutoff and you should be good to go, assuming you are under control otherwise.

I am interested to see if any of this applies to other people's setups. And shucks, if I am all wrong then that's cool, just interested in helping.

I did shoot some incredibly poor video yesterday that I am embarrassed to share. It's mostly for the guys with O2s out of whack so they can have something to compare to. The first is just idle O2, and the second is a couple low boost runs. They are awful and the sound is totally jacked. The camera is a slr so its guts were rattling off the charts. View at your own risk.


----------



## GinsterMan98 (May 19, 2008)

djsheijkdfj said:


> http://www.saxonpc.com/
> 
> I'm going to purchase one of these for my 36# OBD1 setup. Having the same low RPM, partial throttle stumbling/hesitation that everyone else has. I have tested/swapped/replaced EVERYTHING that could be causing this - I pulled my hair out for weeks trying to find a solution before I found out that everyone else with the 36# OBD1 tune has the same problems.
> 
> ...


Yeah, I spelled it wrong. He ships fast too! I have noticed my car is much more stable at low load and engine speeds.:thumbup:


----------



## Corsten (Sep 26, 2005)

'dubber said:


> The straighteners did smooth things out a bit, my zietronix monitors maf voltage and the readout even looked smoother, but the problem eventually came back within a few miles. I think I edited or posted a followup in that thread.
> 
> I took some logs last night in vagcom/ vcds, if I email them to you, can you plot them in excel and post them ?


No idea how to do that, haven't been plotting anything in excell from college, sorry can't help you here.
the one I included here is straight up from VAGCOM. It saves a log in excel format, I think there's also a vaggraph or something that shows live graph data, but I think it just uses same values is saves in excel values to plot it - not sure whether it can be saved in such a graph format or not..


----------



## Corsten (Sep 26, 2005)

GinsterMan98 said:


> Yeah, I spelled it wrong. He ships fast too! I have noticed my car is much more stable at low load and engine speeds.:thumbup:


Did you get one or two? one in front and one in the rear of the MAF? how did you mount it there. I read some people using JBweld. Which ratio did you use and what size for a 4" MAF, is it 100mm, 96mm?, I never measured the inside diameter of the housing.


----------



## Corsten (Sep 26, 2005)

vergessen wir es said:


> So the problem is that under certain conditions the motor doesn't idle right....


I'll try to video my gauges behavior, especially part throttle (30-40%, TPS angle of 29 from vagcom), around 0 boost mode, when the engine hangs around 3500rpms - as highlighted on the excel values I pasted earlier, AFR jumps to 20 or flashes (goes out of scale), and I basically coast with gas pedal still depressed, when I should be still accelerating. So I either need to let go of the gas or press it in even more. I'm not getting this issue at WOT.


----------



## GinsterMan98 (May 19, 2008)

Corsten said:


> Did you get one or two? one in front and one in the rear of the MAF? how did you mount it there. I read some people using JBweld. Which ratio did you use and what size for a 4" MAF, is it 100mm, 96mm?, I never measured the inside diameter of the housing.


I got the 96mm in a 5:1 ratio. I am only running one in front of the MAF. I made my own MAF housing so the MAF is as far away from the turbo as the pigtail will allow. The DV vent is right at the end of the silicone 90 going into the turbo.


----------



## 'dubber (Jun 15, 2004)

I didnt realize vagcom or vagscope could do plots like that, where is that function? Damn!

Yeah Vergessen you are describing what we are experiancing, definately load dependant, always during times when load is light or not there. It may happen more for others than you for whatever reason, but its so frustrating to deal with. I think a lot of us daily drive and cruise around, explaining low rpm driving. I get it between shifts when down shifting, making rev matching very frustrating. So load calcs are based on maf readings, tps, what else? Im looking for a solution that does not require custom tuning, standalone, or driving around the issues. I've been doing that long enough and I think I speak for many others as well.


----------



## 'dubber (Jun 15, 2004)

Corsten I think I went with the 100mm straighteners, I bought one of each so I could try a few combos. I have the metal one shoved in the 4 to 3 silicone reducer, and one of the plastic ones in the air filter so that the clamp holds it as well as the filter in place. Kind of a balancing act with that one.


----------



## vergessen wir es (May 12, 2010)

Are your guys' dashpots on the TB installed and working? You might try giving it more stroke so throttle closing aren't such a shock to flow and also the ecu will have more time to bring the ISV online. Not sure but they might get too quick for smooth transitions when old. Just a thought.


----------



## 'dubber (Jun 15, 2004)

Mine is working and I checked it with 3mm wire. I did try adjusting the screw once and its frozen so i stopped. Maybe a piece of foam over the end to slow it down as an experiment woukd be interesting. 

When I say I'm not looking for custom software, I mean I don't think every person should have to buy dyno time to get it right. Im basically saying that everyone who knows their setup is not flawed otherwise should appeal to the original coder or someone who knows how to write this stuff to come up with a better "universal" version of the product that addresses this issue. I'm not even sure if this issue would show up on a dyno, which is possibly why it was not addressed in the first place. I know, wishful thinking. Obd1 is a small portion of the market, And I'm not anticipating any of the heavy hitters like c2 or UM to come to our rescue and make the necessary changes that would allow for a better universal product. They see a few guys bitching on vortex about obsolete equipment not working correctly. Not a moneymaker for them I will approach and ask soon if there is something that can be done. Maybe something can be accomplished somehow.


----------



## GinsterMan98 (May 19, 2008)

'dubber said:


> Mine is working and I checked it with 3mm wire. I did try adjusting the screw once and its frozen so i stopped. Maybe a piece of foam over the end to slow it down as an experiment woukd be interesting.
> 
> When I say I'm not looking for custom software, I mean I don't think every person should have to buy dyno time to get it right. Im basically saying that everyone who knows their setup is not flawed otherwise should appeal to the original coder or someone who knows how to write this stuff to come up with a better "universal" version of the product that addresses this issue. I'm not even sure if this issue would show up on a dyno, which is possibly why it was not addressed in the first place. I know, wishful thinking. Obd1 is a small portion of the market, And I'm not anticipating any of the heavy hitters like c2 or UM to come to our rescue and make the necessary changes that would allow for a better universal product. They see a few guys bitching on vortex about obsolete equipment not working correctly. Not a moneymaker for them I will approach and ask soon if there is something that can be done. Maybe something can be accomplished somehow.


I think you are 100% on your idea. I think these tunes get stuck bouncing between decel and accel maps, hense the lean afr's and stumble. This issue is not just an OBD1 though, both my OBD2 chips have done it. The 30# was the worst, the 42# is much better after the flow corrector install and my mods to the inlet tract, 4in the entire way.


----------



## Corsten (Sep 26, 2005)

OK, I took a short drive with a stock software today. The symptoms described in this thread related to light throttle operation are non existent. Therefore I dare to say it is the software here at fault. Unfortunately the car did stumble and die coasting to a stop. I guess that happens because of the way ISV is connected and EVAP deleted - just my thought - doesn't matter what software is in. 

I still do get this "hang" when entering boost (gauge at 0) at part throttle - rpms stay around 3500, gauge reads lean (20) and it feels as it's not getting any fuel (as if it's coasting) until I let go of the gas pedal or I go WOT. It's a lot lighter with stock software than with C2. Or maybe I'm not punching on it as hard keeping in mind I run stock chip and I don't really want to enter boost with it. - so I guess I have some issues here. Definitely need to check for vacuum leaks. 
However I don't understand why is it going lean at part throttle when around 0 of boost level. If I had a leak it would have been rich.... 

could it be the spark blowing out and unburnt oxygen causing lean readings ?????? hmm....., but why only at part throttle? 
or...maybe it is unmetered air getting into the system at part throttle?, I don't think ECU is disregarding MAF at WOT, is it? I believe it's disregarding o2 sensor.


----------



## 'dubber (Jun 15, 2004)

Keep in mind that (i'm guessing) you still have upgraded injectors and maf housing installed with your stock software. That will cause all types of weirdness. But I agree that the problems that come up with the c2 chip are due to the codeing related to load based fueling. When you have a good number of people with the same problem and a car that was fine before the install, and no other issues currently, then the last possible suspect is going to be the culprit. For now just put the c2 chip back in and focus on cleaning up your vacuum lines. Get a vac block to reduce tee connections. Also you'll want to unplug that fuel tank vent line or simply reinstall your evap system.


----------



## Corsten (Sep 26, 2005)

'dubber said:


> Keep in mind that (i'm guessing) you still have upgraded injectors and maf housing installed with your stock software. That will cause all types of weirdness. But I agree that the problems that come up with the c2 chip are due to the codeing related to load based fueling. When you have a good number of people with the same problem and a car that was fine before the install, and no other issues currently, then the last possible suspect is going to be the culprit. For now just put the c2 chip back in and focus on cleaning up your vacuum lines. Get a vac block to reduce tee connections. Also you'll want to unplug that fuel tank vent line or simply reinstall your evap system.


 actually I have everything intact. Just switched to stock software. Actually before I put on the turbo I fitted a 4" MAF anf 30lb injectors - just for test, all was running fine with out a glitch. 
As for the fuel tank line, it's not super sealed, so it's venting OK. 
Will need to do leak test.... what's the best to do vacuum leak? I read somewhere to spray carb cleaner???, I was thinking of putting some gaoline in a spray bottle and give it a go, would it work? 



> could it be the spark blowing out and unburnt oxygen causing lean readings ?????? hmm....., but why only at part throttle?
> or...maybe it is unmetered air getting into the system at part throttle?, I don't think ECU is disregarding MAF at WOT, is it? I believe it's disregarding o2 sensor.


 anyone?


----------



## vergessen wir es (May 12, 2010)

Gotta figure there is a reason we don't hear much about spraying raw fuel around looking for vac leaks. Even though carb cleaner is more volatile it has a finer mist so is more effective so less is used and it dissipates faster. Boost leak testing will find most vacuum leaks that are before a check valves. And the vac supply lines leading to a check valves can be blocked for a test. 

So you ran the stock chip with the 36# injectors right, and say it ran fine. Was this on the same ecu? Did you try it with the O2 connected and disconnected? Not sure the AFRs would tell us anything with the stock chip on 4" MAF except that logs would indicate that the O2 is working to adapt. 

Given that you still have this 'hang' around 3500 suggests to me at least that you have a sensor or ecu problem. Looking at the logs you posted earlier, it appears that no outputs (or inputs) are being updated much during that time, even though we know changes are taking place. For example, I doubt throttle angle was fixed for ten seconds. Timing was locked, load barely changed, injector on time is locked, O2 sensor looks disconnected during that time. The ecu is getting implausible inputs somehow, either from outside the ecu or within. This problem, 3500 hang and bad O2s, looks electrical/electronic not chip, especially since it is with either chip. 

These cars are notorious for corrosion in the main ecu connector from a bad raintray. And the corrosion can be hard to see as it is a very fine white powder on top of the tinned pins. Later cars are gold plated so not so much an issue. Some 600 grit on a thin stick can do wonders there.


----------



## 'dubber (Jun 15, 2004)

Forget looking for leaks with gasoline. Really the best thing to do is a PRESSURE test it will reveal leaks that a vac test will seal up and you wont be spraying volitile chemicals everywhere. 

Also tell me specifically how you are getting vagcom/vcds to create those charts so I can make my own and post them up.


----------



## Corsten (Sep 26, 2005)

'dubber: did you get vagcom working for output as per my instructions, or you want me to get those screen shots? 

update: 

I redesigned my vacuum lines so that DV is connected to nipple by throttle body, wastegate to manifold where you guys in US have brake booster connected, and gauge sharing signal with FPR, no more rpm stumble, AFR seem correct, a much more pleasant car to drive, weird, since same setup on stock ECU and software was working fine. 
Anyways, I guess it is a good idea to use a separate vacuum signal for each receiver. 

....going back to the weird 3500rpm hang, or whatever I called it... I did some thinking and listening while driving. Basically when that happens I hear pressurized air going through (as if you're inflating a tire), so when I let go of the gas a little and press it back in it's not there.... 
so my assumption is... my DV is leaking, or not working right, can anyone confirm that? 
I was also thinking that's why I get a lean measurement on my gauge. I have my foot on the gas pedal, 3500rpms, DV opens, air passes through, recirculates back in the intake, but not more fuel from injectors, hence lean mixture..... am I thinking correct?


----------



## Corsten (Sep 26, 2005)

another update.
I have bought a new DV 710N, installed it - no change, installed it in a different orientation... stil no luck, although my old one was leaking it didn't fix my issue.
I just can't seem, to understand how this whole turbo set up works. 

followed the DIY and did test for boost leaks (connected the PCV wplug with a stem at MAF) Checked for leaks without removing front bumper so I didn't check leaks at intercooler yet. So far don't see any.

another thing: Do you guys hear any air passing through while in boost?. I mean you can hear whistling sound for sure of the turbine spinning, but do you hear any pressurized air with that???? I am, and I don't know whether it's a leak or DV valve opening - this is when I get a lean reading on my gauge and the car looses power - only at part throttle when entering boost (slightly over 0 when looking at boost gauge)


----------



## vergessen wir es (May 12, 2010)

What pressure did you test to? If you test from the MAF then the DV has pressure on both sides so you won't be able to detect a leaking DV. When you test from the turbo inlet then the DV is being tested. I am sure you knew that tho.

As far as pressurized air sound...I wonder if you are hearing WG flow.
What WG spring are you using now, and are you modifying that value with a boost controller?


----------



## Corsten (Sep 26, 2005)

well, I didn't know that testing from the MAF side won't test leaking DV, thanks for letting me know, anyhow my DV is brand new. used this site to test it.

I don't have a compressor to test higher pressure, was using a little one that hooks up to the cigarette lighter. Will get proper one hopefully tomorrow.

The thing that troubles me most is that pressurized air sound...... I don't thing it should be there when entering boost, unless it is the wastegate stuck open,... would it be that loud for me to hear it?, 
I can hear it once the pressure builds up, as if there is a massive leak.
Also I hooked up a manual boost controller to see if anything changes when I adjust boost pressure. no change there. actually I can't go past 5 PSI,. no matter how I set it up. I am running a red spring on the wastegate, I guess it is a 5PSI spring.

Why is it that my AFRs read lean when this happens?....


----------



## vergessen wir es (May 12, 2010)

Yeah it takes a lot of air to fill up the manifold and intercooler etc. so a decent size tank (min. 5 gallon) filled with 90 psi and a regulator to control what the motor sees does help. I test to 20 psi since that covers any boost I will run. It can be hard to keep the PVC to stay in above those pressures unless it has a barb.
5 lb is a light spring. You will be hearing WG flow pretty early. Are you running the spiral flex between the WG and the DP? If so then WG flow is audible since it isn't totally sealed. Not saying that is what the sound is, just that is could be.

Getting good even boost control without dips and variation, ie having a WG that opens the right amount, at the right time and can stay there is not easy. And I am getting convinced that the single side port of the kinetic mani is part of the culprit.

But more to the point, the lean thing doesn't make sense yet. I guess I would be looking at fuel pressure while driving next.


----------



## Corsten (Sep 26, 2005)

vergessen wir es said:


> Are you running the spiral flex between the WG and the DP?


I am in fact



vergessen wir es said:


> But more to the point, the lean thing doesn't make sense yet. I guess I would be looking at fuel pressure while driving next.


before I put on the turbo I had the fuel pump checked. Guys at the shop told me that the efficiency was 7 bar (not sure if constant, or a peak value)- pretty good I would say.

more updates.....

I've finally done a boost leak test....... and the results are:
really small leaks on the piping. but after hours and hours of testing I found out that my head leaks!, is that normal? I mean I get a leak probably through the valves (I'm sure some of them stay open when the engine is turned off - am I right?)
pressure leaks through my crankcase where I have a catch can hooked up. This is probably when I hear this pressurized air sound while entering boost... also wastegate is leaking a bit (in the middle, where top and bottom part meet) when the boost controller is closed shut. When turn the knob clockwise (under pressure) I hear an audible pssst, so I guess it is leaking aw well!!!, or is it OK?

guys, tell me, should I be loosing air through my head? is this a normal behavior? 

head was rebuilt about 10,000-13,000 miles ago. When I was putting the spacer in I had the head decked at the machine shop ( I guess it was disasembled when they did that and put back together)


----------



## Corsten (Sep 26, 2005)

bump for answers, I searched but did not find any useful info


----------



## vergessen wir es (May 12, 2010)

Are you suggesting the head is leaking because of air coming out of the PCV? That would be blow-by and some is normal. The only way to tell how much and if it is excessive is with a leak-down test, and might as well do a compression test same time. Sorry....nother couple tools to buy or borrow.

I wouldn't be running a boost controller for now (BC removed, not just turned down). Plus, then the sealing (or lack of) between the WG halves won't matter. I would run off just the spring with the boost signal connected to the bottom port. The top port stays open or filtered. Just one less thing until you are running right.


----------



## Corsten (Sep 26, 2005)

I've already done a compression test and a leak down test before the turbo mod, all was fine. Unless something has changed with a spacer.
not sure how much air should be coming out of the crankcase... but when I bent the hose to prevent the air to leak and unplugged an oil cap, boy was it fun.... 

So the only possibility for me to loose air pressure is the crankcase, I don't see any other leaks anywhere.... tested up to 20-25psi


----------



## 'dubber (Jun 15, 2004)

Corsten said:


> 'dubber: did you get vagcom working for output as per my instructions...


Yeah, I thought that you meant that vagcom was generating the chart on its own without Excel. My old laptop did not have Excel on it, but now I have a better laptop that has Excel so the files open right up. 

Did you just screen-capture to post your data or is there some other way to do it?


Also, if you were pressure testing before the pcv tube, that will pressurize the crankcase.


----------



## Corsten (Sep 26, 2005)

Yeah, I just used print screen and saved it to a file.

as for pressure testing, I tested at compressor inlet, so I guess it will pressurise the crankcase and the air will vent through my oil catch can, don't know however how much of that air is supposed to be escaping through it.... seems like a lot of air is escaping there.


----------



## Corsten (Sep 26, 2005)

bump for ideas,....maybe someone has already encountered a similar issue....


----------



## masterqaz (Oct 5, 2007)

if your pressure testing the piping through too the head id expect you to hear leak through to the exhaust, their will be valves open in at least 2 cylinders at any given time iirc.


----------



## Corsten (Sep 26, 2005)

that may be true, however I experienced much more of an air leak through the crankcase.

had no time to work on the car past few weeks. Hopefully soon I will start working on it again.

The list includes:

reworking ISV connection directly to the charge pipe off the compressor.
trying different set of plugs, 
different set of injectors
doing a pressure test
replacing TPS

will see if any of those help
oh, and I installed the air straightener for the MAF.

any other ideas are more than welcome


----------



## Corsten (Sep 26, 2005)

I have redesigned my ISV connection, it's connected to the charge pipe right after turbo. Installed the flow straightener. I also exchanged manual turbo controller with a brand new one The car runs MUCH MUCH better I am able to build boost up to 15 PSI. She pulls hard at WOT all the way to redline, but bogs down at steady part throttle (kept at the same position, no foot movement - see the file) just right after it enters boost. 
Here is a clip of how it looks like









When it happens here's how it looks from the ECU perspective












CAn anyone help?, is ignition timing OK? what about injector duty cycle?


----------



## 'dubber (Jun 15, 2004)

It looks like you are stuck in open loop, based on the o2 sensor and tps readouts. Based on my own experiments, my car has the tip in problem with or without a working o2 sensor. But i noticed it so thought i would point it out. I'll say that there is zero interest in any further refinement of our software via the original programmers or the new programmers at the original company. I will be installing standalone, prolly lugtronics for the support because i dont really understand all of the adjustments that will be possible with the standalone.


----------



## Corsten (Sep 26, 2005)

you mean the ECU is not switching between fuel maps? - is that running in open loop?


----------



## 'dubber (Jun 15, 2004)

The o2 sensor readout is staying on 1 which it should only be doing near or at wide open throttle. This means that during part throttle and idle the ecu is only using preprogrammed fuel values and not relying on the o2 sensor readout to adjust fueling towards a 14.7-to-1 afr.


----------



## Corsten (Sep 26, 2005)

Are you sure this is also the case with C2 software?, I think they might have modified it so that ECU takes 02 into account up to whatever rpms or engine load....I'm just speculating here.... Do you have a readout of your vagcom for c2 software to confirm/deny this? how does it look compared to mine? maybe you can share....

funny thing is...ecu shows the O2 reading 1 (rich) whereas wideband shows lean...WTF?

when I look at the readout from ECU, O2 values seem out of whack, but when driving the car AFR show the right mixture all the time, I don't get it.....also, when I disconnect o2, it's super rich....
I'm not following then.....seems like ECU doesn't take O2 reading into account during normal driving, but does so when it's disconnected?


----------



## kushdubber (Jun 8, 2010)

is this why i should convert to obd2?

gl


----------



## 'dubber (Jun 15, 2004)

I can email you some logs, and then you can look at them and post up anything from them if you want to. I suck at trying to use excel and screen captures so if you PM me an email address I'll just send you some logs. 

The earliest c2 software was written so that the o2 sensor was intended to be physically unplugged at all times. Then it was changed to operate more like stock software with the o2 sensor plugged in and utilizing open and closed loop fueling. As far as I know, open loop (pre-programmed fuel maps) is used during wide open throttle or close to it, heavy engine loads. Closed loop (using narrowband o2 sensor input to tweak fueling) would be used during part throttle, light load conditions. My logs should indicate this and again, I'll be more than happy to email them to you and you can look at them and post them up here if you want to.

Yes, switching to OBD2 is an option. You can also consider something like replacing the stock maf with a PRO MAF. I want to do standalone because I can get away from using a MAF sensor and go to a MAP based system, and it will be much more tuneable. I think that's better for my needs, as I still hear of people with issues even with maf based obd2 setups or obd1 with promaf. At this point for me to do an obd2 conversion or pay for a promaf and still have issues I would not be happy, so I'd rather just go standalone and pay a little more and get a lot more out of it for the time, effort, and money.


----------



## Corsten (Sep 26, 2005)

ok so I PMed you my e-mail adderss for the log file. Will have a look at it. 

I also PMed Jeff Atwood on here about my case, because I'm a bit desperate, since I haven't driven the car since last year, but he did not respond


----------



## magner (Jul 26, 2009)

do yourself a custom tune buy an ostrich2 emulater 

disable the 02 in the software 

disconect the battery short leads together to discharge the ecu to clear adaptations before new tune 

dont bother with tps leave it unplugged 

there is just one 24x24 fuel map to tune if using c2.. set idle afr and boost afr to what ever you want takes about half hour to tune 

i can help you with above and with checksums after your happy with the custom tune for your setup


----------



## magner (Jul 26, 2009)

Corsten said:


> you mean the ECU is not switching between fuel maps? - is that running in open loop?


obd1 c2 does not switch between fuel maps it uses 1 large map 
original software uses 3 fuel maps idle part and full throttle maps 

looks like you c2 software already has the 02 disabled the 1 in the the 02 logs means no trim plus or minus is being made to keep the afr at 14.7 . when you unplug the 02sensor itself the ecu is seeing it is not there and dumping fuel in to save the engine from melting


----------



## Corsten (Sep 26, 2005)

hey, thanks for your input.

Basically I've started a new thread here http://forums.vwvortex.com/showthre...hrottle-low-boost-lean-issue-obd1-c2-software

after many test and diagnosis the issue I'm having is somewhat software/tps related. Not sure exactly what it is.

Few important things:
1. The car is a EURO vr6 using a US EM/BM ECU with corresponding C2 software. (as far as I know the only difference is SAI and EGR between European and NA vr6's)
2. Changed the MAF from earlier 6pin to newer style 4pin MAF
3. EGR and SAI have been coded out of the software (thanks to this 14.7 AFR at idle and cruising, no CEL)
4. Car runs fine when EGR and SAI coded out but issues as described in the thread when part throttle into boost.
5. When using original file US C2 file (SAI and EGR in place) I get fault codes, AFR out of scale at idle, car dying at idle, but running fine at boost and half boost
6. When using stock ECU from a later European vr6 (designed to run with a 4pin MAF) I get EXACTLY the same symptoms as the modified C2 software (EGR and SAI coded out) - meaning, issues part throttle when in boost)
7. Car won't start and run with TPS disconnected when cold
8. Runs fine without TPS when warm, dies when coming to a stop

I think it might be TPS related (new one is in - same thing happening) - I will follow wiring diagrams in order to check for pin signal differences for TPS between earlier vr6's vr newer ones, I hope this is the problem

Could be that O2 has been coded out at particular load/rpm by C2 - not familiar with it, so it still has to stay connected?

I'm not familiar with Ostrich 2.0, nor do I know how to use it, would have to learn how to do it. I heard that C2 fuel map uses only one big one...

well this is what I am struggling with, - all the help is more than welcome...


----------



## magner (Jul 26, 2009)

if you decide to learn to custom tune i will help setup tunerpro rt to live data trace your fuel so you can richen or lean your fuel at different load points while your driving but you will need one of these 
http://www.ebay.com/itm/Moates-Ostr...Parts_Accessories&vxp=mtr&hash=item43ac8dcb80
good luck dude


----------



## magner (Jul 26, 2009)

i have the crappest 3gp video ever dunno if you can even see it off on old nokia 6630 

the fuel trim adaptation is deleted. afr at idle is 14.9 with 630cc injectors 

you see the yellow highlight moving about this is what part of the fuel map it is using at idle 

i can raise and lower the number in these boxs i can set my idle afr anywere from 10.0afr to 

19.0 afr with a click of a button. when drive your car the yellow highlights move further across the map i cruise about 

15.2 afr to save fuel 

View My Video


----------

