# '98 Jetta 2.0 (1H) Throttle Body Alignment ERROR



## mwysienski (Apr 5, 2011)

Hey guys, I'm wondering if my TB is shot and needs replacing. I bought this car a few weeks ago and the idle was fine, maybe a bit low, but no CEL. I did what I always do when I get a new (to me) car, change the oil, air filter, fuel filter, spark plugs...all that stuff. Since it felt like the idle was a bit low, I tried cleaning up the TB with a little TB cleaner. Idle went up to about 1400-1500 rpms and the CEL kicked on. 

These codes came out:
P0510 Close Throttle Position Switch
P0507 IAC Revolutions
P1582 idle calibration at limit (er something like that)

At this point I took off the TB and cleaned it up like it was brand new again. Slapped it back on and now my idle is about 3000 rpms. That's when I learned that a TB alignment was due after such a cleaning. So I bought a VAG-COM K11 w/USB. I did the whole, "Select", "01 - Engine", "Measuring Blocks - 08", group "098", "Go!", "Switch to Basic Settings"...thing. This is what I get:

Thottle Pot Voltage 1 - 4.260 V
Thottle Pot Voltage 2 - 3.560 V
Operating Mode - Part Throttle
Basic Settings Status - ERROR

Meanwhile the TB just sits there doing nothing. If I pull up on the gas pedal (forcing the TB to close, more like it should be) before going into Basic Settings, I get these values:

Thottle Pot Voltage 1 - 4.340 V
Thottle Pot Voltage 2 - 3.560 V
Operating Mode - Idle
Basic Settings Status - ERROR

Then I'll hit "Switch to Basic Settings" and the screen will show these values while the TB is cycling through something (note, values are now in red):

Thottle Pot Voltage 1 - ERROR
Thottle Pot Voltage 2 - Group 098
Operating Mode - Not
Basic Settings Status - Available

The TB will go back to being slightly open, as if the TB was very dirty. The TB alignment is either not happening or is happening incorrectly. If I am already sitting in Basic Settings with the very first values I posted above (suggesting I'm slightly pushing on the gas...but I am not) saying "part throttle", aaaand I quickly pull up on the gas and let it go, these values flash for only a fraction of a second and another faux TB alignment seems to be happening:

Thottle Pot Voltage 1 - 4.460 V
Thottle Pot Voltage 2 - 3.900 V
Operating Mode - Idle
Basic Settings Status - ADP. Run

I think these last values are what I want to see, right? But nothing changes after the TB goes through whatever cycle it's doing. It still idles around 3000 rpms. 

Also, this might be the way it is supposed to be, but the led light on the cable that plugs into the car flashes from green to red back to green really fast over and over. This happens anytime the "Open Controller" window is open. So I'm not sure if that just means that it's communicating or that there's something wrong.

Can anybody help me? I need to definitively pinpoint this problem before I go off buying all types of things like expensive new TBs. 

Oh another thing... My CEL has turned off recently. I can get it to come back on by disconnecting the battery for a while. I think that it's going away either because: 1 - I'm driving around with my foot underneath the gas pedal so I can pull it up to bring my idle down to the low to mid 1000s, or 2 - the TB is dying, thus not reporting the codes back to the ECU anymore. Those are just hunches, not proven.


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## Dana @ Ross-Tech (Sep 15, 2009)

The last portion when the TB is actual attempting to adapt is promising. I added a DBC note about the throttle cable here, have you checked the tension or cable for failing/sticking?

Flashing of the LED is normal to indicate status/activity.

Post the complete Auto-Scan if you need further assistance with this.


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## [email protected] (Mar 18, 2011)

Ahhh the ABA. I'd start by clearing the faults in the ECU using your VAGCOM even if there aren't any faults stored. Then, disconnect the positive and negative posts from your battery and connect the leads together for approx 5 minutes. (the LEADS not the posts) This is called a capacitive discharge. This will delete the ECU's learned values. Now, reconnect your battery and try adapting the throttle in basic settings 98. If it Errors out, keep trying 98 over and over. Seriously, I have done this numerous times and works. Once you get it to say ADP OK, do it few more times. This will sweep the contacts of the potentiometer and clean up any dull spots. BTW, check and make sure your throttle cable is seated correctly. You shouldn't have to hold up on the pedal to lower the RPM. Hopefully this works for you. Don't buy a new TB until trying this. Good luck to you.


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## mwysienski (Apr 5, 2011)

ya know.... I looked at the throttle cable before doing any of this. I must not have looked at it that well because I couldve swore that it was not adjustable. I know that sounds kind of dumb...to engineer a throttle cable that isnt adjustable...but I just kinda figured that was part of VW's quarky style.

It turns out that it was too tight. I took it down a couple notches last night and I am much happier now with a normal idle. However, I think there is still something going on with the TB. I noticed that I can't get a WOT reading in the vagcom. Both flooring the gas pedal and holding the TB wide open with my hand at the butterfly fail to give a WOT signal to the vagcom. It only shows "idle" or "part throttle".

Thanks for the suggestions! Tonight I'm going to go home and try 'em out.


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## [email protected] (Mar 18, 2011)

A throttle adaptation will give the ECU information regarding the throttles beginning and end stops. Once a successful adaptation is completed, you should be able to get a 100% throttle angle with the pedal on the floor. If not, we'll continue on looking at other possible causes.


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## Uwe (Jan 16, 2000)

Yep, on a cable-throttle car, a cable that's too tight (i.e. has no play) can (and probably will) cause a TBA to error out.

I disagree with expecting to see 100% throttle opening in the measuring values on that engine. My fuzzy recollection of M5.9 ECUs (from my VR6 days a decade ago) are that they will never show 100%.

-Uwe-


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## [email protected] (Mar 18, 2011)

You're thinking of actual throttle angle. And you are right, it will only show like 86%. But it will show 100% in the requested field. I'll nail down the MVB. I have an ABA out back here at the shop. Were you a tech? Do you remember the test plan? It was weird. You had to slowly increase the throttle while watching the MVB in 10 degree increments and recording the voltages.... This and if it was an automatic trans, at kick down the last digit of the binary changed from 0 to a 1 and the throttle read 100%. I'll get that info and post it. I have to go now as my brain is starting to catch fire....


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## [email protected] Parts (Nov 27, 2006)

This content VACATED and moved by Jack :heart:
I recommend to see the RT forum directly for intelligent conversation.


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## [email protected] (Mar 18, 2011)

Ok, so the ABA out back is a 95. So no dice there. The MVB's are starting to run together after 12years...

Jack, well said! The carbon ring build up can definitely be a problem. All of that info was right on.


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## mwysienski (Apr 5, 2011)

Hey Grant, first off, thank you to you and everybody else who is trying to help. I don't know if you were asking me if I was a tech or somebody else... but no, I was not. Just spent a lot of time fixing my cars because I can't buy new ones. (Most of the time I enjoy it) On that note, what's a "MVB"?

I didn't post the auto-scan cause I thought my first post went beyond that while taking up less space. But I will re-do the auto-scan and post it. I'm not sure what's going to come up though cause my CEL isn't lit anymore, and I cleared the codes. At one point there was something that came up about a...throttle position voltage too high...or something like that. I'll try to grab that info this weekend. Easter is going to make it difficult though...

Well last night, I tried the capacitive discharge and then attempted the TBA over n over...n over. No improvement, but I did notice that at the time when it looks as if the TBA might run (ADP flashes), the throttle valve does dip backwards before moving forward. I also checked the reverse movement of the valve by hand. It seems to move freely but takes what I thought was a surprising amount of force from my thumb to push it. It will go all the way shut. I can hear it tap on the wall of the TB as it closes all the way, by hand as well as during attempted TBA. I cleaned the hell out of it when I took it apart. I don't think it can get any cleaner.

Jack, is "01-04-098" different from "01-08-098"? ..or does that just imply skipping the measuring blocks part and going right to the basic settings (sorry I don't have it in front of me). Is ground supplied in the wire harness? I figured since the engine is grounded, that the TB's sensors were grounded to the TB itself...no?

FYI, the 17990 code doesn't sound familiar. I don't think I had that one.

Another thing that came to mind last night was that I hope my instrument cluster isn't fogging up the VCDS's view of the throttle body. The temp and gas gauge always work but the speedo and tach only work intermittently. unrelated right?


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## [email protected] (Mar 18, 2011)

You are very welcome. MVB is "measure value block" in VAGCOM. And yes, there is a big difference between 01-08-098 and 01-04-098. 04 means that you are Basic Settings. The throttle adapation will NOT take place if you are in 08 Measure Value Block. You must be in Basic Settings (04) for the procedure to function. 17990 is a very common throttle body error code. The tester (VAGCOM) will read "17990 Idle adaptaion at limit". I believe Jack was refering to this earlier. And he is right, many people and even VW Techs have replaced throttle bodies when it was not necessary. I have cleaned the carbon ring that builds up inside the throttle housing and applied a drop or two of 3 in 1 oil (light oil) to each side of the throttle plate. And after a discharge to delete the ECU's learned values, the adaptation took and my faults never returned. Now if you were trying over and over and over in "measure Value block" (01-08-098) this explains why it never passed. Try it again in Basic Settings and see what happens (01-04-098).
And no worries on the cluster interfering with the throttle. There is no CAN BUS in this vehicle. The 98 Passat, I believe, was the first VW to have it. Your car communicates by K wire only and only to a select number of module, the cluster NOT being one of them. Let me know how it works out.


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## mwysienski (Apr 5, 2011)

Ok, that's something I didn't know about the CAN BUS system...sounds like more of an open network throughout the car. The 17990 code sounds like the P1852 code that I had earlier in during the first post that I made. I did attempt the ADP in basic settings. As I understand it, Measuring Blocks are just for viewing values, and Basic Settings are mainly for performing an act of some kind. I wasn't just sitting there staring at the Measuring Blocks for hours...lol.

About lubing up the valve... If I've already cleaned it up spotlessly, and I can see the valve move backwards to that "5mm offset" that Jack brought up, what ideas does that spark up? Is it specifically 5mm or is that just an estimate? I think maybe it moved a little less than 5mm.


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## [email protected] Parts (Nov 27, 2006)

This content VACATED and moved by Jack :heart:
I recommend to see the RT forum directly for intelligent conversation.


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## mk1wideboy (Jul 20, 2011)

mwysienski. Did you ever find out what the fault was, and if so, how did you fix it? I'm having the same problems with my 2000 polo 1.4 16v.


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## mwysienski (Apr 5, 2011)

Yea, I did...and I meant to make a nice helpful writeup of the whole ordeal. I just never got around to it. I haven't forgotten. One of these days...

It turned out that the previous owner never cleaned out the throttle body. It got pretty gunked up, to the point where the throttle body had adjusted itself all the way to the position to increase the idle...but it wasn't enough. Ignorantly he/she manually upwardly adjusted the throttle cable. So after I had cleaned out the throttle body just for regular maintenance, the idle went super high. Then I spent all the money and time trying to do a Throttle Body Alignment, all the while it wouldn't even perform the process because the cable was too tight and restricted the movement of the butterfly. It just kept showing errors.

Overall the steps I took were:
- Take throttle body off
(do not take plastic black cover off, this part is not serviceable)
- Clean thoroughly with throttle body cleaner and toothbrush
(if real bad, can speed up process by starting with softer wire brush..be careful not to scratch)
- Reinstall throttle body
- Lightly lube friction points of butterfly with oil
- Adjust throttle cable as tight as possible while still being able to get a closed throttle position
- Run TBA
- Let the wind whip through your hair

You don't have to take off the throttle body to clean it, but it makes it easier to work on the TB and to get it **** and span. I think I would've been ok without the TBA, but I had the equipment at that point... I felt really dumb when I finally saw that the cable was too tight. You really can't overlook the little things. 

I'm not familiar with that 1.4 16v motor. Is that a turbo? Cause that could be a whole different can of worms.


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## mk1wideboy (Jul 20, 2011)

It's normally aspirated.

I put a post on the forum:

http://forums.vwvortex.com/showthread.php?5371706-Polo-1.4-16v-AHW-idle-throttle-problem

but to date no one has replied. Its looking like a faulty TB or ECU. 

I've had the TB off and cleaned it. Have tried TBA now more times than I can remember, even with the throttle cable disconnected. I just get ERROR every time.


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## mwysienski (Apr 5, 2011)

Try this first before looking for a new TB. I was told to lube up the butterfly, and I thought that was ridiculous at first. The butterfly seemed to be so free moving that I didn't see a reason to rub oil on the part I just cleaned the hell out of. ...but I was wrong. 

There's a bit of movement in the reverse direction. I think about 3 or 4 mm. Get a Qtip with a little bit of new engine oil, and work that into the two points where the butterfly are held in place. Then, you gotta get your thumb in there and keep working it in that direction, back and forth, back and forth. Do for longer than you think you need to. Then go back and try the TBA. Do it all with the TC disconnected.

If that doesn't work, I'd assume it's not clean ENOUGH. I'd say if you can see any black around those two pivot points, keep that tooth brush moving.

This area of the forum is probably better for your problem. The smart guys will chime in soon for you.


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## [email protected] Parts (Nov 27, 2006)

Thank you for actually listening!!!!!!


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## GearheadBRD (Apr 4, 2009)

*TBA Error*

Thanks for all of the tips & excellent tech info guys. I could find no mention 
made of free play needed when adjusting the throttle cable in my OE Bentley
manual or OnDemand Online. All they say is to remove clip, hold throttle to 
WOT & adjust cable. Which is exactly what led me to this problem. Found the 
thread & kept backing off the throttle cable one notch at a time & retrying ADP.
Finally got it to set properly. Major Kudos to VAGCOM too! Well worth the
investment as few independent shops in my area have the right diag tools
for VW & Dealer is @ $110 /hr labor. You guys are the best!


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