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woolveren
04-04-2013, 06:42 PM
Hi All,

My car's(98 A4 1.8T, 250K miles) fuel pump died last week on highway throwing couple of errors for throttle body adaption failures, which were 17972 and 17973. I've replaced the fuel pump with a new VDO pump and the car is up running again.

But just now I've noticed that the car is slowly gaining some RPM when engine is idling. When I start the car, the needle settles around 900 rpm, but then after couple of minutes or so it goes to 1000~1100 rpm automatically. But in between if I hit the gas pedal for a second, idle goes back to 900 rpm.

Also, I've observed that the RPM needle is kind of slow to come down to zero when shifting. In the past, it used to get back to zero quickly between shifts.

The guy who was fixing my car had cleaned the throttle body initially assuming it was a bad throttle body because of 17972 error. He cleaned the throttle body and re-adapted it through vag-com. It did adapt fine and later we found out that it was a bad fuel pump preventing car from starting.

My car never had this engine idling issue. Can this be due to an improper throttle body alignment?

Also, at one point I've noticed that the car took one or two more cranks to get started. No CEL's.


Please advise.

Wet0willy01
04-04-2013, 06:50 PM
Mine did this, also with TBA failure code thrown. I tried to adapt and it failed, then threw another code for not reaching a closed position. Replaced my throttlebody and did the TBA. Fixed.

walky_talky20
04-04-2013, 07:42 PM
Perhaps it just needs adapted again. I'd try that. No go? Then I'd try to clean it and adapt it again. Still no? Then you might be looking at replacing it.

Make absolutely sure you don't have any vacuum leaks as well. A leak into the manifold will obviously raise the idle just as if the throttle body opened a bit. And make sure your throttle cable has sufficient "free play" in it and is moving freely. A sticky or over tightened cable could also cause what you're describing.

woolveren
04-04-2013, 07:54 PM
Mine did this, also with TBA failure code thrown. I tried to adapt and it failed.

But my car's the throttle body adapted absolutely fine after getting those errors. [confused]


Perhaps it just needs adapted again. I'd try that. No go? Then I'd try to clean it and adapt it again. Still no? Then you might be looking at replacing it.

Make absolutely sure you don't have any vacuum leaks as well. A leak into the manifold will obviously raise the idle just as if the throttle body opened a bit. And make sure your throttle cable has sufficient "free play" in it and is moving freely. A sticky or over tightened cable could also cause what you're describing.

Car doesn't have any vacuum leaks, pretty much all the hoses were replaced last yr and everything looks good. Also I saw that free play in throttle cable, but was thinking it was loose. LOL. Even the guy(not a regular mechanic) who was fixing my car thought it was not normal and said he will look into it while cleaning throttle body. So not sure whether he tightened it now. :) Have to check it tomorrow.


How can I adapt the throttle body using Vag? I only have the VCDS lite version.

Can we do TBA without vag? I remember seeing somewhere in the past that we can do TBA by unplugging battery and waiting or something..?

Wet0willy01
04-05-2013, 03:26 AM
But my car's the throttle body adapted absolutely fine after getting those errors. [confused]

Then you're good. Didn't realized you were able successfully complete the TBA. Sorry

QuattroGinger
04-05-2013, 04:08 AM
i thought we could do TBA without vag. something like holding down gas pedal for X seconds while ignition is on then starting car. something like that. ill try finding info

QuattroGinger
04-05-2013, 05:02 AM
found this. didnt finish reading since at work but might be helpful

http://www.audiforums.com/forum/diy-do-yourself-55/audi-a4-b5-throttle-body-alignment-problem-not-aligning-rough-idle-hunting-idle-160531/

Sveke0021
04-05-2013, 05:04 AM
I had this. Was a simple vacuum leak.

Sent from my Galaxy Nexus using Tapatalk 2

woolveren
04-05-2013, 05:42 PM
i thought we could do TBA without vag. something like holding down gas pedal for X seconds while ignition is on then starting car. something like that. ill try finding info

As I said above, I remember seeing somewhere doing TBA without VAG.

This is what I remember, disconnect battery, wait for 10 minutes, .....................remaining steps I don't remember (:


found this. didnt finish reading since at work but might be helpful

http://www.audiforums.com/forum/diy-do-yourself-55/audi-a4-b5-throttle-body-alignment-problem-not-aligning-rough-idle-hunting-idle-160531/

Thanks for the link. This tells about TBA by VAG only and seems like I need to have a full version to do this.

QuattroGinger
04-05-2013, 06:18 PM
http://www.audizine.com/forum/showthread.php/113722-B5-A4-Easter-Eggs!-Features-not-found-in-the-owner-s-manual/page2

Post # 51 talks about it as well. Found steps o audi world earlier but can't find link now


EDIT: http://www.audiforums.com/forum/audi-a4-8/easter-egg-audi-secrets-tips-86233/

Hope one of these helps