# Question about Boost Leak Corrado



## erickramirez (Aug 2, 2008)

*UPDATE: this thread is kinda long so here is all the information you need to know about whats been done so far. if you need more details then read along. and a big THANK YOU to all the people who have helped me out and just the vortex in general! anyways.... 

Boost tubes ARE tight (have been pressure/leak tested up to the throttlebody by me and a respectable shop with no leaks) 

I no longer have the Eurosport Tubes so the Co pot is not leaking 

Belt is not slipping (have BBM adjustable tensioner and belt has been tightened correctly by shop) 

TB return is not leaking (Tested 2 different TBs and they were both good, with no affect on boost) 

Fuel injector O rings are not leaking (replaced them, originals werent in bad shape either) 

ECU to TB vac line has been replaced and is the correct length. 

The only thing that hasnt been checked is the Intake manifold Gasket, and a few vac lines, but im leaning towards gasket because: i remove the OEM boost tube that holds the co pot, and i connect my boost leak tester (cap with valve stem) then i set the motor to TDC and revert 3 teeth, THEN i hold TB at WOT, THEN i cap off the valve cover breather (ive also left it connected but no difference) Then i proceed to pressure test with my air compressor (good one). 

Boost gauge reads a max of 4-5psi (sometimes it will spike up to 8 at the verrrrry beginning but then goes down and levels at 4-5) i can hear a noise from the intake manifold/fuel injector area. Since i replaced the O rings, this leaves me with the assumption that it has to be the Intake Manifold Gasket.... 

Compression Test Results: 

1. 126psi 
2. 116psi 
3. 129psi 
4. 130psi 

everything points in that direction....i have not checked timing..but i might cough up some money and have the gasket replaced. 

anyways thank you all for your time and please chime in with your thoughts and i will update when there is more info. 
* 

So Ive had a Boost leak in my car for a long time now and i still cannot find the source of the leak, i just Checked ALL my boost tubes including the intercooler from the Outlet of the charger to the Throttlebody, Everything is TIGHT and i cannot see where there would be any leaks there, i pressure tested the intercooeler and it was good, i tried pressure testing from outlet of charger to throttlebody using the homemade pressure testing method (but i used a ball pump instead of a bicycle pump) and i sat there for a good 3 min pumping with no pressure building up. i have a KnN Cone air filter that makes a boost leaky noise, could a bad KnN cause a boost leak (im losing about 11psi btw). My boost gauge reads about 2-3psi never higher, and i used the MFA to measure boost as well and the highest it got was around 170ish, and at idle it was 155-167. my boost gauge is reading off a eurosport boost tube right before the co pot, so does that mean my leak is somewhere beatween charger outlet and throttle?? plz help  ask me questions i will try to answer them. some info on the car: brand new charger, stg 4 chip, rsr outlet, carbon canister delete, PS delete, AC delete, ISV re route,


----------



## G'D60 (Mar 11, 2002)

Could the return butterfly valve in your throttle body be locked in the open position? If it is the boost would just recirculate right back to the charger, blowing on the K&N. Maybe yank the throttle and play with the linkage. Make sure the dump valve is closed when you move the linkage to the WOT position. 

Good luck


----------



## erickramirez (Aug 2, 2008)

i have thought my throttle body might be bad, so lets say it is locked in the open position, if i were to place a BOV inbetween the co pot and the throttlebody, would that fix it? cuz i had a previous set up where i had a BOV and i was making 14psi. now with this set up i can only make 3psi max, and when i floor it in 3rd, 4th, 5th, and sometimes 2nd, i get very little response, the rpms will take FOREVER to climb its really hard to redline in 5th, and also idk if this has anything to do with this, but when my gas pedal is half way to the floor, it makes a clicking sound. but anyways i want to yank the throttle and play with the linkage, how do i go about doing that?


----------



## DigiMatrix (Apr 16, 2010)

Have you read the Bentley procedure - leak test A. It involves placing the cam at TDC for cylinder 1and then turning the camshaft back 3 teeth by rotating the crank counterclockwise. Pull the inlet (air filter) side to charger pipe and make a blocking plate with a tire valve stem in it. Block the crankcase ventilation pipe to the charger. Then presurize at the valve stem and look for the leaks. This method leaves all boost pipes intact including the intercooler. I used a regulator and compressor, slowly increasing the pressure to about 15 psi and then used a soapy spray bottle to look for leaks. 

The procedure says increase to 0.9 bar, shut valve to compressed air source. The pressure after 30 seconds must not be less than 0.3 bar


----------



## erickramirez (Aug 2, 2008)

Ok before I go and buy a compressor, is there any other way to check if my throttlebody is faulty? I removed the hose on the inlet so I could look at the butterflies as a messed with the throttle, so when I move it to half throttle, the return butterfly closes halfway and the smaller butterfly opens halfway, and at wot the bigger butterfly and the smaller one both open fully, and the return butterfly closes fully, but while I have it at wot I can put a little pressure on the left side of the return butterfly and it will open, is this normal, and is there anything else I can do to test my throttlebody before buying a compressor?


----------



## erickramirez (Aug 2, 2008)

ok i am almost positive my problem here is the return butterfly, like i said earlier the previous owner had a BOV installed, as soon as i removed it, problem started, so how do i fix the return butterfly? is there a way to tension it? new TB? i dont want a BOV in my car


----------



## G'D60 (Mar 11, 2002)

Yes I'm pretty sure you can adjust the throttle body. you'll have to yank it off, (4 allan nuts) the big boost tube and the return line at the bottom of the TB, ECU hose and Carbon canister. its a bit of a pain if you have big hands but its a neccassary evil. When its off you'll be able to see the linkage. IIRC there are 2 nuts on either side of the linkage that you'll have to play with. I would move the linkage to the WOT position and make sure that return line gets tightend HARD in the close postion. you could put a little thread sealer on it to keep it in place. Chances are its slipped in the past and maybe thats why the PO put in a BOV, who knows... 

I'm going to play with my spare TB tonight and see if i can manually push open the return valve in the TB when its in the WOT position. I'll let you know


----------



## erickramirez (Aug 2, 2008)

Ok thank you so much for ur help, I will get started on removing the TB, those bolts seem to be on there pretty good. Ill let you know what I find out on my TB and if you could tell me what u founf out on your spare that would br great,


----------



## Sr. Karmann (Feb 5, 2009)

erickramirez said:


> Ok thank you so much for ur help, I will get started on removing the TB, those bolts seem to be on there pretty good. Ill let you know what I find out on my TB and if you could tell me what u founf out on your spare that would br great,


are you using these?


----------



## G'D60 (Mar 11, 2002)

SO. I played with the TB yesterday. There should be no play in the return valve when the TB is set to WOT. I'm not sure where the issue is on your TB but it might have to do with the springs that move the butterfly valve. 

Here is a pic of the TB looking at the return valve. It has 2 springs which load and unload when the TB is at WOT









Sorry for the mess, didn't clean up the old TB before pix. Here is another shot of both springs. they seem to be wrapped 5 or 6 times.



















Compare it with yours and let us know what you find.

Good luck!

OH and you can see the linkage adjustment in the first pic. Its hella greasy but there are nuts at the bottom of the metal 'L' shape link. they are attached to plastic retaining caps.


----------



## erickramirez (Aug 2, 2008)

Yes I was using those and finally got it out  now upon further inspection I believe I have found the problem, when I hold it at WOT next to the springs, right where the end of the outermost spring loops and grabs on to the metal, I think mine broke, and the rason I am able to easily move the return butterfly when at wot is because that metal is not holding the springs tightly, its hard to explain but I will post a pic after this post ( I'm on my phone) and hopefully it will clear things up. Please let me know if mine is indeed broken, if it is would welding it together fix it? Here comes the pic


----------



## erickramirez (Aug 2, 2008)

ok so right where my finger is pointing, that is the metal i am talking about, i believe it should just be one piece, not 2




when moving the throttle cable all the way to wot, these 2 metal pieces stay together all the way to wot, where at the end they seperate just a little bit as shown in this pic



so the reason i can move my return butterfly so easily while at wot is because the bottom of the 2 metal pieces is not connected to the top of the 2, so when i push on the butterfly, the bottom piece moves back towards idle position, while the top piece stays put. If this piece was originally just one piece, this problem would not exist correct? am i making sense?


----------



## G'D60 (Mar 11, 2002)

I'm a little confused. I'll have to look at mine again and compare. I'm wondering if the tension on the spring is the problem. When there is pressure comming from the charger it pushes on the dump valve, if that spring is worn or weak, the boost could pry open the dump valve slightly allowing boost to escape... 

I'll go home and take pix from the same angle you took your pix. maybe we can do a visual comparision and see if that "two peice" metal thing should actually be one. and if there is a small gap at wot.

Just to clarify the first picture is the TB untouched (idle position) the second picture is the TB at WOT. If so I'll take the same pix tonight.

Good luck!


----------



## erickramirez (Aug 2, 2008)

Yes you are correct, first pic is idle, second pic is WOT. So if for some reason those 2 pieces that i think should be one, actually come in 2 pieces from the factory, then what can i do to adjust the springs? the linkage adjustment wont tighten them would it?

And if mine is broken, would JB weld hold the 2 pieces together? i went on their website and it says their stuff can hold up to 3,000psi??


----------



## erickramirez (Aug 2, 2008)

Hey GD60, so you say when you hold the throttle at WOT, and you try to move the return butterfly with your finger, it will not move at all? And did you say you had an Extra TB? If possible I would not mind buying yours if you are willing to sell, if so let me know, thanx


----------



## G'D60 (Mar 11, 2002)

Hey man.

Yes I can open the return line slightly when its at wot. it does not open very much tho. a few MM. not enough to let out 14PSI of boost tho...

I took a few more pictures from different angels last night to show you what mine looks like. Now that I think of it I shoulda made a little video so you can see. Maybe i'll do that tonight and host it on youtube. anyways here the pics. 

First pic shows 2 peices of metal









This pic shows both springs and the hooks that attach to the metal









Another shot of both hooks









another angel









I think that last pic was me moving the linkage to WOT thats why its blurry. lol.

If you want the TB I'll let er go for 50 plus shipping if you want. 

Hope the pix help!


----------



## erickramirez (Aug 2, 2008)

Hmmm I think I'm missing one of the 2 hooks u showed on the 2 and 3 pic, and maybe that's why mine opens at WOT (I can completely open the return butterfly while still holding it at WOT) so I'm assuming the job of those 2 hooks is to keep it from opening, ill check mine when I get home, if that's the case and I can't fix it I might buy yours, thanx man


----------



## G'D60 (Mar 11, 2002)

Cool man! hope you can figure it out. I wonder if you can buy parts for the TB. like a new linkage, SPRING ect. I know you can get new wot and idle switches. who knows...

Let me know if you want me to youtube a video for you this weekend. I'd be more than happy to help!:beer:


----------



## erickramirez (Aug 2, 2008)

Hey so actually nothing was missing on my TB, but the springs did seem loose so i tightened them up to the point where i could no longer push open the butterfly when holding it at WOT, so when i took it for a drive i only gained about 2psi, so now im making 5psi. im still missing about 9psi and i still think it has to do with my TB, so im just going to go ahead and buy yours, how much would it be shipped 3 day select to 98346?? and what is your paypal? thanks


----------



## G'D60 (Mar 11, 2002)

Hey man.

Gonna check out shipping today. I'll get back to you!


----------



## erickramirez (Aug 2, 2008)

well installing the other TB helped but did not solve the problem, i am now making about 6psi. the only possible thing that it could be now is my intake mani gasket, correct? i also heard from somewhere that too many boost tubes would slow down the build up of pressure, but i think thats kind of a long shot, i have 2.5" tubes and im running them the only reasonable way to run them for a FMIC.


----------



## RedYellowWhite (Apr 21, 2008)

erickramirez said:


> ... i also heard from somewhere that too many boost tubes would slow down the build up of pressure, but i think thats kind of a long shot, i have 2.5" tubes and im running them the only reasonable way to run them for a FMIC.


I think the routing of the IC piping DOES have an affect in boost pressure, and that routing seems kinda long to be honest...I also read an old thread on Vortex about how a FMIC will appear a drop in boost (just like a p&p head or a really agressive cam will)

***See how an oe Rallye FMIC is routed for reference (use of u-bend)


----------



## erickramirez (Aug 2, 2008)

Fair enough, re-routing the plumbing tomorrow, i will update soon.


----------



## erickramirez (Aug 2, 2008)

So i got rid of the long a$# plumbing i had, and did sort of a U-bend (more like a 90 degree bend) at the outlet of the charger which made me get rid of about 4-6ft of plumbing, took it for a test drive and now im making about 7psi... so im half way there, car still feels super slow as far as low end torque, above say 3.5k rpms it picks up but im still missing another 7psi. before i replace the intake manifold gasket i am going to have it pressure tested and see what that brings up


----------



## dubbin69 (Oct 2, 2006)

please inform us of what you found out... i am kinda in the same position as you are dont mean to thread jack


----------



## G'D60 (Mar 11, 2002)

Did you get the Throttle body okay? did that help with the boost loss?


----------



## erickramirez (Aug 2, 2008)

Yup got the Throttlebody, it did give me like 1-2psi of boost more so at least it helped.




dubbin69 said:


> please inform us of what you found out... i am kinda in the same position as you are dont mean to thread jack


i havent really found anything yet, the only things i have done so far is change the throttle body (the return butterfly on mine wasnt working) and shorten the plumbing. the only things left i think could affect my boost are:
Intake Mani Gasket?
Clutch slip? i havent gotten any symptoms of it tho.
Would low Cylinder Compression affect boost?
I noticed a very very slight gap between my charger and the BBM RSR, is there a torque spec on the bolt?
And lastly for some reason my charger could be bad, but im 99% sure its not cuz its just recently been rebuilt (i do see slight oil residue on the RSR outlet but ive heard thats normal)


----------



## dubbin69 (Oct 2, 2006)

erickramirez said:


> Yup got the Throttlebody, it did give me like 1-2psi of boost more so at least it helped.
> 
> 
> 
> ...


i have a slight oil residue also... and herd thats normal also... my return butterfly was very loose tightened it up but still seems a little loose but not as loose as before... i gained about 1-2 psi off that now all my gaskets are new as the motor was completely rebuilt and punched to a 1.9 and head work was done. what i read was that will also affect boost but i shouldn't be running 3-4 psi


----------



## jetta52 (Nov 22, 2009)

I know that you said the the charger was rebuilt, but you might want to crack it open anyways,or send it out for inspection. Seems like you have done everything else. Worth a try.


----------



## erickramirez (Aug 2, 2008)

so im bringing this back, i finally got around to properly compressing the whole system for leaks, i have a bbm air intake which is 2 pieces where the air filter goes so i just removed one of the pieces and pressure tested from there (set 1 cylinder to TDC and moved back 3 teeth.) 

so when i pressure test it my boost gauge reads only about 5-6psi. so i definately have a boost leak somewhere, sprayed down my boost pipes and they were all good to go so that leaves it at somewhere between the throttlebody and the cylinders right? i could HEAR a noise coming from from somewhere in the Fuel injector/intake mani area but i could not feel anything nor spraying it down with water/soap make any bubbles.. 

also while we were testing we kept letting the compressor compress cuz air was escaping so we thought it wouldnt hurt to let it on, somebody was watching the gauge at all times and it never went anywhere above 6psi, and then all of a sudden we heard a sort of pop noise and more air escaping (this time it sounded like it was coming from the block???) and the gauge fell down to 0. decided to stop the testing for the day, drove it home and it was driving normally (making 6-7psi) so idk what happened there?? 

today i took off the vacuum hose for the boost gauge just for the hell of it, and at idle it does nothing, and anywhere up to 1/3 throttle the little hose will SUCK air in, and then past 1/3 throttle it will blow air out, which will give me my reading of 6-7psi. so does my boost leak have something to do with throttle? or was it just doing that cuz it was disconnected? 

lastly, if im losing 7psi would it most likely be the intake mani or the o-rings on the fuel injectors? and would a clogged cat make me lose boost? (mine is making noise) 

i know this is long but if anyone cares to help me out i would really appreciate it. TIA


----------



## G'D60 (Mar 11, 2002)

Dang man. dang. 

I dont 'think' you can loose 6-7 psi from the injector harness. although anything is possible. i'm sure you put a little soapy water around the o-rings. A clogged cat would impead flow out the exhaust thus heating things up. If its a bad clog, your exhaust mani should start to glow. Not sure if that would have an effect on boost. 

Did you ever find out what that 'pop' was? Hows the intercooler? end caps on tight? no holes (had to ask) everything bolted up okay? ie intake manifold? My buddy had a corrado with poor boost. it turned out the PO tried to replace the intake mani gasket and couldn't get all the studs in. left a slight gap where boost leaked. I dunno. 

I'm sure you checked all your vac lines and replaced any that were old and frail. the ECU line has to be 1M long. i'm sure thats been covered somewhere in the thread. 

Ummmm. Man I can't think of what this could be. I was sure it would be the TB. I feel bad that it didn't work out for you!! 

Keep us posted man. We'll figure it out somehow!


----------



## Svedka (Jul 4, 2008)

I had this issue in my g60 2 times before I got rid of it. 


1st compression test your engine if there is a intake leak you will have low compression 

2nd have the gladder inspected


----------



## erickramirez (Aug 2, 2008)

bringing this one back, AGAIN! i just know my G lader is good, it doesnt make any noise, no extra oil, and it was rebuilt by a really well known rebuild company (KK). im going to add another detail to this mystery: when im driving and the trottle is idk, anywhere under 1/3 throttle, it sounds normal. but then when its anywhere in the MIDDLE area of throttle(when it should be making boost), there is this weird noise that sounds alot like its coming from the firewall area. the first thing that comes to mind when i hear that noise is air escaping, and THEN past the middle area of throttle and towards full throttle i will more than likely always hear a whisteling noise coming from that same firewall area. this HAS to be my leak. i took my car in the a really highly praised shop and they tested the whole INTAKE system from TB to charger, and checked/tightened the belt. i asked them what they thought about checking for compression in the engine but i didnt really get a reply. SO hypothetically lets say this #@%# leak is somewhere past the TB, and its making noise towards the firewall area. WHAT are the possible culprits to this? Intake mani gasket? Injector O rings? i need all possible culprits because i am just going to replace everything that COULD BE, and pray it fixes this problem.

even with 5psi of boost i still get minivans beating me at take off at red lights... :facepalm:


----------



## Svedka (Jul 4, 2008)

Svedka said:


> I had this issue in my g60 2 times before I got rid of it.
> 
> 
> 1st compression test your engine if there is a intake leak you will have low compression
> ...


I'll quote myselfopcorn:


----------



## erickramirez (Aug 2, 2008)

Svedka said:


> I'll quote myselfopcorn:


isnt pressure testing the cylinders essentially the same thing as a compression test? i already did that so i dont want/need to do a compression test because i know i will have low pressure like last time, and when i did it last time i could HEAR the air escaping but i could not pin point it even spraying water, thats why i would like to know what the possible culprits are, past the TB. and as for inspecting the G lader, it cannot be bad, especially since i know theres a leak since i can hear it.


----------



## G0to60 (Jun 23, 2003)

Have you checked the vacuum line that runs into the cabin that goes to the gauge cluster? I had mine T'd for a boost gauge but didn't have it fastened tight so it leaked really bad.

Are all the vacuum ports on the intake manifold capped or being used?

Everything else I could think of has been mentioned. Good luck. :thumbup:


----------



## erickramirez (Aug 2, 2008)

G0to60 said:


> Have you checked the vacuum line that runs into the cabin that goes to the gauge cluster? I had mine T'd for a boost gauge but didn't have it fastened tight so it leaked really bad.
> 
> Are all the vacuum ports on the intake manifold capped or being used?
> 
> Everything else I could think of has been mentioned. Good luck. :thumbup:


vacuum ports on the INTAKE MANIFOLD? i dont recall seeing any? i know i capped off all the ones on the Throttlebody. the only vacuum port i remember on the Intake mani is the one for the FPR and the one on the front (which is capped), where is the other ones? and that vacuum line that runs to the cluster, where does it connect to on the engine bay? because i remember having to remove a vacuum line that was T'd off close to the firewall when i did the CC delete, but instead of removing the T and just joining the remaining 2 lines, i cut the extra 3rd line and just capped it off, i hope that makes sense


----------



## G0to60 (Jun 23, 2003)

Sorry, I did mean the throttle body. I'm not sure the routing of the gauge cluster vacuum line. It will come out of the firewall on the driver's side and I think attaches at the throttle body or T's somewhere close to there. I'd have to look at my engine bay to know for sure.


----------



## GTIXXX (Sep 16, 2004)

I was an original owner of a G60 for 11 years and was always chasing down boost leaks.

Hopefully you didn't remove the hose from the intake manifold to the ECU (MAP sensor).

Under certain conditions the ECU will dump boost through the ISV. I used an Autotech Boost check valve
to cure that. I believe that you stated that you had a ISV reroute. I would recheck that.

Also on my Eurosport Hi Flo boost tubes where the port is for the CO pot, I had to use 2 O rings to stop
a leak.

Hoses could have a split that is not noticeable until they are under boost then open up.

Most of the hoses at the intake manifold rot over time and leak.

Also I would make sure that the G charger doesn't have bad seals and is actually producing boost.


----------



## erickramirez (Aug 2, 2008)

GTIXXX said:


> I was an original owner of a G60 for 11 years and was always chasing down boost leaks.
> 
> Hopefully you didn't remove the hose from the intake manifold to the ECU (MAP sensor).
> 
> ...


i did not remove the ECU hose, but i have yet to replace it.

i had the eurosport boost tubes (like in the pic) and i thought that could have been a source of the leaks even though i doubled the o rings, so i swapped it for the OEM boost tubes, and still nothing.

most of the hoses in the intake mani/TB area are new/seem new, but i will replace the suspicious ones (not that there are any in particular.)

i have been driving the car with the isv plug unplugged and its running fine (maybe better when it comes to idle) so i might just delete it and cap off that area, we will see if that has any affect on it.

i still cant get over the fact that it makes such a weird noise in the middle of the throttle, i swear i hear air escaping, its definately not a noise that should be there. i either think its Air(80% leaning towards this) or gas (20% leaning towards this) but i doubt i can hear gas, it just sounds weird, and my stupid exhaust is too loud so i cant really post a vid, but when driving its SO CLEAR from inside the cabin (if i point it out to you). and it is DEFINATELY coming from the TB/intake mani/ firewall area.....  

theres still some things i need to check (vacuum lines, etc.) hopefully i can get to that this weekend...
i cant believe ive been driving on 5psi for a year now..!


----------



## erickramirez (Aug 2, 2008)

ok so i replaced the ECU line (1 metre) and the line goin from intake mani to FPR, NO DIFFERENCE. 

also tried a ISV delete, car would NOT idle, sat there for some 10 min givin it a little gas and as soon as i let off it would sputter and die. so i put the ISV back (but still have it unplugged and idles great that way :what: )

there is one more vac line i will replace, i doubt it will make a difference though. otherwise as soon as i get some more money im sending it off to a shop to get the engine pressure tested or something.


----------



## erickramirez (Aug 2, 2008)

ok i have a new symptom now.
it used to be that my car would have no power in the low end (1000-2000) and good power (for only makin 5psi) above 2500rpms.
now i have good power at the low end and its really hard for me to get it past 3000rpms. i mean i can get it up there but it used to be that i had to shift soon cuz the rpms would climb fast but now they dont seem to do that anymore.
EXAMPLE: my car cruising at 50mph in 5th gear used to be at 3000-3100rpms. now its at 2400-2500rpms. weird i know.
i think i know why though, recently my clutch has been slipping, but only when i floor it. it will disengage for a second until i let off the gas then it will catch again. this has happened maybe 5 times now. 
also the gas pedal gets super firm about 2/3rds of the way down.
and the whistleing noise seems to have stopped, but i can still hear air escaping (like letting air out of a tire)
i know that is obviously bad but it honestly drives better now(but still making 4-5psi), but i definately have to replace my clutch soon.
anyways didnt know if this had anything to do with it..


----------



## G'D60 (Mar 11, 2002)

Not sure about the clutch. Only reason is I had something similar happen to me on my GTI. WHen I was crusing and wanted to punch it, i thought the clutch was slipping and not bitting enough. It would hesitate for a sec until I backed off on the throttle and then it would pick up and go. I thought my clutch was slipping.

While replacing the clutch i got in there and saw that everything looked real good. Real meaty. I was dumbfounded. COuld have SWORN it was the cultch. For whatever reason the motor was jacked up at an awkard way (either jacked up to remove tranny or we lowered subframe, i can't remember) When looking around the engine bay i noticed my intake boot had a nice rip on the underside that was only visible when the motor was being jacked. The movment of the motor while being jacked allowed for the hole inthe intake elbow to been seen as it was sitting at a strange angle. turns out that the hesitation was due to the vaccum leak. When I tried to get on it, the hole would open up bigger cuasing the hesitaition. Paid big cash to replace a perfect clutch :banghead:

I'd like to say it has somthing to do with vaccum but I'm sure by now you've replaced every vac line in the car. Your issues just sound so strange. I really wish we could figure this thing out and get you more than 5 PSI.

Have you ever run a boost tube right from the charger stright to the TB and by pass the IC? The only reason why I ask is that woudl be a good way to see if there IS a leak around the IC. If you see 12 PSI with the direct boost line, you know you have a leak at the IC. Any chance that ur end tanks on your IC are cracked? it would be real hard to see with the naked eye, but they would flare up under boost... 

I just dont know what to tell you man. 5psi is not right. never. there has to be a leak somewhere along the line. do you have an AF guage? I'd have to assume your running pig rich with the lack of boost going into the motor. how do your plugs look?

Hope this helps.


----------



## erickramirez (Aug 2, 2008)

well i know my clutch is bad (theres alot of other symptoms too) i just didnt know if it was related to the boost leak, might not be.

everything from the charger to the TB is air tight, i tested it, shop tested it, smoke tested it. i have pondered bypassing the intercooler just for the hell of it, but i wasnt sure if it was safe or not.

replaces all but one vac line, all the lines i replaced seemed to be in perfect shape though so im assuming the one i havent replaced is in good shape too, will replace when i get more line from dealer though.

i can still hear that air escaping noise, keeps making me think its intake mani gasket or maybe fuel injector seals? no tools for me to test that though, although i did water and carb cleaner test it and got nothing.

i am running rich, replaced spark plugs a few weeks ago though, got a little better.

also replaced o2 sensor, Black and Blue CTS.

i keep thinking back to how this all happened: charger needed rebuilding, sold it and bought another one that i thought was rebuilt, wasnt so i sent it off to be rebuilt, while being rebuilt i removed carbon canister and BOV, and installed new IC piping and intercooler, got charger back, installed, 5psi of boost.

an interesting note: i guess my chargers displacer was too damaged to be rebuilt, so they had to scrap that half of it and get another half from another charger with a good displacer and use that. sometimes i wonder if they scrapped the wrong half of the charger....but i doubt that.,,hmm... like i said i can HEAR the leak! so it cant be my charger!

thanks for the advice GD60, i appreciate you following this thread!


----------



## marcscott.designs (Mar 1, 2010)

I had a similar problem on my g60. Intake manifold gasket was shot and I was loosing 12 pounds. Another thing you might want to check is your exhaust valves. On my old g60 the valves wouldnt close all the way, didn't show out of spec on a compression test but was enough to loose boost at lower rpms. Valve cover breather is another place you can get a leak. The intake manifold gasket is a weekend job, if you're mechanically inclined it's not too bad just get ready for some busted knuckles. You might as well replace the exhaust manifold gaskets while you're at it. Worst case scenario the charger wasn't rebuilt right and I think Kk isn't doing rebuilds right now since he's out of country still. Good luck, don't give up


----------



## erickramirez (Aug 2, 2008)

marcscott.designs said:


> I had a similar problem on my g60. Intake manifold gasket was shot and I was loosing 12 pounds. Another thing you might want to check is your exhaust valves.


 

Thank you that's exactly what I've been wanting to hear, if the intake manifold gasket could make me lose that much boost, and according to you seems like it can, and with all my symptoms that seems like the number one culprit. Would a compression test test the intake mani gasket? I'm assuming it will. 

Also how would I go about checking the exhaust valves? Thanks.


----------



## erickramirez (Aug 2, 2008)

Still fighting this thing.
So i finally borrowed an air compressor so i can actually take my time and look for the leak properly. i followed the steps to close all valves by aligning the 2 dots on the camgear and then turning it back 3 teeth, and also holding the throttle at wot(anyone care to explain to me why this last part is needed?). when im testing it i hear a very clear leak coming from my oil cap. air is just coming out of there and if i kind of press down on it it will seal up better but air still leaks.also i noticed that that area is always a little wet from oil because (im assuming) oil leaks out from there and the overflow hole. so how do i go about fixing this leak? i bought a brand new oil cap and nothing (it didnt look the same as my previous one, maybe not oe, could that be it?) maybe it just doesnt fit right? also i have a powdercoated valve cover, could that have anything to do with how it seals? i did try searching oil leak boost cap air all kinds of combos and nothing.


----------



## Geoff-60 (Aug 29, 2011)

In a past post u said yo had the isv unplugged and it ran great.. as far as I know and someone correct me if I'm wrong. Unplugged the isv stays open. You could be losing bost here. Also when you delete the isv it will idle like crap. You must set the idle manually with the idle screw on the tb. This being said. Check that screw check its o ring and check if its loose or wobbky. I have seen up to 5lbs on the mfa being lost because of that scrw. I have my isv deletex and idle at 900-1000 but its cold here in colorado. Hot areas u can set to 750 850 and be fine


----------



## erickramirez (Aug 2, 2008)

ive experimented alot with the ISV, i was running with it unplugged, and it ran and idled fine after a min of warming up, but i got tired of having to feather the gas so i just plugged it in a gain and have been running with it plugged in for 2 months now, runs the same. i tried deleting it completely a while ago but it would just not hold an idle, and i have also swapped ISVs with no difference. as far as the idle screw it fits fine and the o ring is new. i have set my idle with it so it is unscrewed a little but not too much. i am positive i am not losing boost through my ISV/idle screw.

still wondering about the oil cap tho. before i go and buy a new one, is it possible to lose boost through the oil cap?

as far as pressure testing the system by lining up the cam gears 2 dots etc, what if its a couple mm off? its hard to fit my head in there and line it up perfectly but ive got it where i believe it should be.


----------



## G'D60 (Mar 11, 2002)

There should always be some positive pressure comming out of oil cap. It shouldn't be too strong tho. enough if you were to unscrew the cap leave it sitting in the housing, it should dance around and shake in the housing. Thats with a normal working PCV system(positive crankcase ventilation) maybe there is something there but I kinda doubt it. How much pressure is comming out of the opening from the oil cap in your opinion?


----------



## erickramirez (Aug 2, 2008)

well when i test for pressure with the air compressor, at first i was leaking at the co pot (no o ring which i was sure i had an o ring before..) and i fixed that and then i started leaking at the oil cap. when im pressurizing it i can hear it fairly well, and i can feel it if i put my palm over it. im not too good at estimating pressure but it is similar to blowing lightly on your hand. my boost gauge read 6psi. im sure there should be pressure there, but im guessing the oil cap should be air tight right? there is also oil coming out of the overfill hole and trickling down the lip of the valve cover (since the cap isnt air tight, might be blowing the oil out?)


----------



## G'D60 (Mar 11, 2002)

Right I forgot you did a pressure test here. not sure how the system should act while doing a pressure test. When the car is at idle the charger makes minimal boost and the pistons create a vacuum but there IS a slight amount of pressure that you can feel comming out of the oil refill hole when you take the cap off. sometimes you'll even get oil droplets. this is all from what I see on my car (fairly stock) and thats at idle. 

I kinda thought the pressure test was simply pressurizing the boost system. charger to IC, IC to TB.

I've never done one so I really dont konw whats invovled. I just thought you'd plug off the one side of the charge and plug up the end of the throttle body and pressurized that way. any leaks on the system would show.


----------



## erickramirez (Aug 2, 2008)

hmm maybe the oil cap thing is normal then.

yeah ive had the boost system (charger to TB, capping off at TB) tested both by myself and by a shop, and it is air tight. that is why i am trying to test the whole engine for leaks by closing all the valves etc.

i know one thing, the leak is past the throttlebody, i have always guessed it was the injector O rings, or intake mani gasket. maybe my air compressor doesnt have enough power to pressurize the whole system? it pressurizes itself to 80psi and then i release it all into the engine thru the air intake. ive changed a couple things in my car since i started this thread maybe il update with new pics and maybe someone can spot something who knows.


----------



## erickramirez (Aug 2, 2008)

OKKAAAAYYYYY FOLKSSSSSS i think i found the problem....  
this time i tested from (essentially) the Throttlebody and on, closing all the valves. anyways when filling it with air i was messing around with the injectors and i noticed that if i touched them air would escape! well i was only messing with one of them (cyl 1 or farthest to left) so im assuming its the same for all 4. but air was definately escaping from there. SO after years of dealing with this damn leak i think im just going to send it off to the dealer to get the O rings replaced. i would do it myself but i heard seating the injectors or whatever was a PIA and/or that you needed some sort of special tool? VW quoted me $184 for the job so that doesnt seem bad. my only question now is while VW is in there should i have them do any other maintenance? my car bucks/hesitates when i let off the gas so maybe my injectors need cleaning? anyways im gonna get this done within the week so i will be back with results........pleasepleasepleaseplease leakbegone!

PS. resprayed the car


----------



## erickramirez (Aug 2, 2008)

well well well....it wasnt the o rings on the injectors. i had the "old style" greentop injectors which have a spacer-oring-spacer setup, and the bottom spacer on every injector broke in half so i had to buy another set of spacers that matched as close to possible. i believe they worked. my o rings werent even in bad shape, some had a few scratches on them but non were chewed up. anyways swapped them and NOTHING. same as before. from what i can tell they are seated correctly and all. think im just gonna go ahead and swap the intake mani gasket just for the hell of it and see where that gets me.


----------



## 2925 (Dec 11, 2007)

Try a new oil cap, they are relatively cheap and a part of the vacuum system. Get your ISV fixed, used ones aren't especially hard to find.


----------



## tedsg60 (Oct 11, 2011)

I have been following this with great interest. Because I have an airleak noise around the throttlebody area also. Yesterday i decided to find it. This car is a new project I just brought home.I looked around the throttle body and noticed a piece of brass setting on the silver cover around the wiring harness. I pulled it out and it turned out to be my idle screw. The rubber cap was over the hole that it goes in. So I screwed it back in and it ran a little better. It makes me wonder what else I will find. 

Good luck on your quest.


----------



## vr6 beats you (Nov 6, 2003)

Interesting read. What's the status on this? I'm wondering, as someone mentioned above, if part of the problem is a pressure drop across that HUGE fmic. This would not explain the noise you seem to be hearing, but have you tried reverting back to the stock ic?


----------



## JBETZ (Feb 17, 2000)

Not sure if this was mentioned here....I didn't read the entire thread.

With no disrespect to Eurosport at all.... I love those guys. There tubes can leak at the co pot sensor bung. You need to double o'ring here. Please also read my response the belt slip thread. Good luck and have a great weekend.


----------



## erickramirez (Aug 2, 2008)

It cant be my intercooler...i had an even bigger one before with no problems, and ive seen people running waay bigger ones with no problems.

and i do not have the eurosport tubes anymore, back to OEM. so alls good there.

i also already have BBMs billet tensioner and belt tightened correctly 

ALSO i updated my Original post with all the main points (that i can remember) from this thread. thank you all for helping me throughout this crazy journey, i just want it to end already! so i can enjoy my G60 again..


----------



## erickramirez (Aug 2, 2008)

alright i finally did a compression test on the car here are my results:

1. 126psi
2. 116psi
3. 129psi
4. 130psi

biggest difference is between cyl 2 and 4 (14psi difference.)

I read that the intake manifold gasket could cause a low compression reading, which brings me to 2 possible solutions:

1. The above numbers are True and my engine is a little worn out.

2. OR my intake manifold gasket is leaking, causing my boost leak and low compression readings??

Either way i think i am going to replace the Intake Gasket just to see what happens.
Ill update again when necessary.


----------

