Ever since I picked up my 1998 Audi A4 V6 Quattro it has had a strange problem. The car runs great except for two things.

1. When coming to a stop the idle drops to about 400 RPM for maybe 2 seconds and then kicks back up to about 700 RPM. Feels like the car is going to die and then recovers

2. This weekend I had to back up about 100 feet and when I came to a stop the car had died. Strange stuff. No check engine light.

Anyone know where to start? O2 Sensor? Fuel Management problem? The car has about 98K miles on it and I have an extended warranty to 100,000 but the dealer wants $125 just to look at it and who knows if the warranty will cover. Anyone know where to start? Thanks in advance

- Mike

 

Is it a manual? #1 sounds like your clutch may be going and it is only engaging at the last second. I test drove a B5 with 50k+ and i felt something quite similar and it was definitely the clutch. Just a thought - good luck man.

 

look for an independent audi shop. i would recomend you change your fuel filter anyway. audi says they are a liftime part...ya right. it is not an expensive part. prob 1 might be an o2 sensor they are a bit expensive to replace. so make sure they need to be replaced first. i think prob 1and 2 are the same prob. it prob is an o2 prob. i dont belive these two parts are covered under any warentee. to check codes your self look io buying one of these vag com. most automotive chains (autozone,pepboys.ect) can do this service free of charge.

 

Sorry. I forgot. Its an Automatic.

So an O2 Sensor sounds like something a muffler shop would be able to do. I think I'll try to get a diagnostic done first and then go from there.

It did just pass smog so could it still be the o2 sensor?

 

WOW. I knew about Vag interfaces but I didn't know there was an in-expensive version available for the average PC User. I'm in the process of buying this right now. This is a phenomenal tool. Also great is I can change my own oil now and reset the change oil code. woo hoo. This is awesome. But more importantly I can find out what is bothering my audi in terms of stalling.

Thanks for the awesome help.

 

This is classic for a dirty throttle body. Run some good fuel system cleaner through it, and then do a throttle body adjustment.

 

Ok. I got a Ross-tech and ran a diagnostic and this is what I encountered: Anymore help on this would be greatly appreciated.

On a readiness test i found:
Evaporative System Monitoring: Failed or incomplete
“Under readiness� – Evaporative emissions – Failed or Incomplete

And a full scan of the car revealed this:

Address 01: Engine
Controller: 4D0 907 551 AH
Component: 2.8L V6/5V MOTR AT D02
Coding: 06251
Shop #: WSC 26107
1 Fault Found:
16890 - Idle Control System: RPM Lower than Expected
P0506 - 35-10 - - - Intermittent
Readiness: 0000 0100

Address 02: Auto Trans
Controller: 8D0 927 156 BQ
Component: AG5 01V 2.8l5V USA 8511
Coding: 00000
Shop #: WSC 00000
1 Fault Found:
00526 - Brake Light Switch-F
27-00 - Implausible Signal

and lastly. Does anyone know what this all means?:

Address 35: Centr. Locks
Controller: 8L0 862 257 N
Component: CV-Pump D06
Coding: 16140
Shop #: WSC 06335
7 Faults Found:
01367 - Central Locking Pump Run Time Exceeded (Likely Leak)
35-00 - -
01371 - Alarm triggered by Door Contact Switch; Driver's Side
35-00 - -
01374 - Alarm triggered by Terminal 15
35-00 - -
01370 - Alarm triggered by Interior Monitoring
35-00 - -
01369 - Alarm triggered by Hood Switch
35-00 - -
01366 - Opened Due to Crash Signal
35-00 - -
00956 - Key 2
09-00 - Adaptation Limit Surpassed

thanks for the help.

 

Alarm codes can be cleared.

Others I don't think should contribute.

I still think that this may be a dirty throttle body. May need to clean the throttle body with throttle body cleaner and then perform a throttle body adaptation.

 

Excuse my ignorance. I've had mostly old chevys with carbs. Would the procedure for the throtle body adjustment be in the bentley manual? And do you have any recommendations for throttle body cleaner?

Thanks.