S6 cold start idle stumble

[Ed Kellock]

Seems like about the time that the ecu would switch between open and closed 
loop with the O2 sensor. 
 Which sensor did you install? If a generic, which brand and did you splice 
or solder?
 Seems to be a consensus that generics are ok as long as they're still Bosch 
and soldering bad, crimping good.
 Ed
 PS. how many times have you started the engine since replacing O2 sensor? 
You might try resetting the ECU memory to erase any bad learnin it still 
gots.

 On 9/7/05, AUDIJIM at aol.com <AUDIJIM at aol.com> wrote: 
> 
> Hey guys,
> 
> I have this 95 S6 that had a cold start idle stumble about a week ago. I
> replaced the O2 sensor and the ECT sensor. That cured about 95% of the 
> problem.
> Now, after about 30 seconds after the first start of the day on a cold 
> engine, I
> get a little idle stumble like before, but not as severe. This morning,
> before I started the car for the first time, I removed the Air Idle 
> Control valve
> and cleaned it out with carb cleaner. But I installed a known good spare 
> AIC
> valve from an AAN I have on an engine stand I started the car and it 
> duplicated
> the stumbling idle. So I reinstalled the original AIC valve. I'm now 
> looking
> for ideals on where to turn, I need to stay focused on my job search and 
> can
> afford the time being spend on this car. I have no problem trouble 
> shooting this
> problem if I had the time, I'm looking for someone who has BTDT. The 
> Audifans
> Knowledge Base does not have this as a topic, but I will add it to the KB 
> as
> soon as I find out what the problem is! I will be in and out of the house
> today, but anyone who has any info on this, please feel free to call me at
> 856.482.1645 or my cell at 856.577.3132.
> 
> Thanks in advance for your help,
> 
> 
> Jim Furdyn
> 1983 UrQuattro #170
> 1987 4000cs Q
> 1987 Euro 200/5000cs TQ 284,000 miles
> 1996 A6 Quattro Avant
> 1987 Mercedes Benz Truck model 1219