[V8] Intermittent High Idle Speed

[Kneale Brownson]

Why don't you put the procedure you posted, along with the parts info, in
the Knowledge Base on Audifans.com?

At 10:37 AM 11/3/2005 +0000, radek at istar.ca wrote:
>Do you live in the rust belt?  It could be a sticking accelerator shaft.  It 
>sits in two
>bearings 
>that can get rusty.  With the engine off, move the throttle and then release, 
>listening for a "click" from the TPS.  Does the shaft return to the "click" 
>position 
>quickly and easily?  If not, you probably have to replace one of the 
>bearings, a $20 item.
> 
>I posted a procedure some time ago and should still have the part number 
>if you need it.
>Good luck.
>
>Radek
>91 V8Q 5-sp.
>88 90Q
> 
>> Message: 5
>> Date: Wed, 2 Nov 2005 20:27:56 -0600
>> From: "Carol, Dave, and Zach Weiss" <cdzweiss at charter.net>
>> Subject: [V8] Intermittent High Idle Speed
>> To: "V8 List" <v8 at audifans.com>
>> Message-ID: <000501c5e01e$33ef7920$b302a8c0 at default>
>> Content-Type: text/plain;	charset="us-ascii"
>> 
>> For those that love a puzzle--  ;)
>> 
>>  
>> 
>> When coming to a stop, clutch in, engine speed occasionally catches
>> somewhere between 2000 and 3200 rpm (usually closer to the low end).  "Idle"
>> is rock solid at those times, just high.  Revving the engine has no
>> effect-engine returns to whatever speed it's seemingly trying to idle at (at
>> the time).  Turning the car off returns the idle to normal.  The engine runs
>> well other than this-plenty of power, no misses, etc.
>> 
>>  
>> 
>> I let my mechanic look at it, and he at first thought it was the accelerator
>> cable.  I didn't see how that would explain the off/on reset, and sure
>> enough, although there was a definite hitch in the cable, the problem is
>> still there after replacement.
>> 
>>  
>> 
>> Now he says it's a combination of engine speed sensor (he got an
>> intermittent code, although I don't know which one) and a slow ISV.
>> 
>>  
>> 
>> Seems like speed sensor or slow ISV would cause idle to be erratic.
>> Sticking ISV or throttle plate should cause code 2231 idle adaptation out of
>> range.  Could this be the idle switch (but if so, wouldn't it cause a 2121)?
>> If not, is it likely an ECU problem?
>> 
>>  
>> 
>> Recently rebuilt top end eliminated excessive oil consumption.  Ned's chip
>> has been installed for years.  Only other problem has been an occasional
>> miss on lift throttle that disappeared after a new O2 sensor, long ago.
>> 
>>  
>> 
>> Dave Weiss
>> 
>> '91 5-speed
>
>
>_______________________________________________
>Audifans V8 mailing list
>Send posts to: mailto:V8 at audifans.com
>Manage your list connection: http://www.audifans.com/mailman/listinfo/v8
>Have an Audi V8 question?  Check the Audifans Knowledgebase!
>http://www.audifans.com/twiki/bin/view/Audi/V8
>Have a V8 answer? ... Please help others by adding to the KB ... all 
>contributions welcome!