[s-cars] 1995.5 S6 now running rough after warm up

[Cody Forbes]

I was going to say it sounds more like a vacuum leak. That fuel pressure though is way too high, so could be an FPR failure.

-Cody Forbes (mobile)

On Jan 19, 2014, at 12:27 PM, "Jerry Scott" <jerryscott at wispertel.net> wrote:

> Jeff
> Your problem sounds more like a coil failure than a fuel pump.
> Jerry
> 
> -----Original Message-----
> From: s-car-list-bounces at audifans.com
> [mailto:s-car-list-bounces at audifans.com] On Behalf Of Jeff Postupack
> Sent: Sunday, January 19, 2014 8:08 AM
> To: S-Cars; Jeff Postupack
> Subject: Re: [s-cars] 1995.5 S6 now running rough after warm up
> 
> I installed a fuel pressure gauge during debug and I see about 60 PSI
> idling, and when I open the throttle, it momentarily drops to ~ 55psi, then
> builds to 70 psi..
> this seems pretty abnormal. Don't ever remember seeing this variation on the
> Pearl S4
> 
> Frankly I'm just looking for the push and confirmation to JFDI.
> 
> fuel pump that is.. Just Freakin Do It.
> 
> 
> On Sun, Jan 19, 2014 at 9:44 AM, Jeff Postupack
> <jeff.postupack at gmail.com>wrote:
> 
>> Gents.
>> 
>> My old trusty winter  Blk/Blk S6 is now suffering in the barn.  157K 
>> miles Stage 1, stock all else
>> 
>> I do try to keep up on preventative maintenance, but I may have 
>> procrastinated too long on one particular item.
>> 
>> After a near flawless 720 run NH to PA- NH last weekend, it developed 
>> a misfire under boost around Jan 14th  It got worse and worse, until 
>> it was easy to debug on Thursday.
>> 
>> I isolated that pb to a single Bosch spark plug, however I changed 
>> them all to new NGK BK7RE. being suspicious (The Bosch I removed were 
>> the tri-electrode, forgot the P/N)
>> 
>> After plug swap it ran strong up until Sat morning.. when it started 
>> running so rough that I would not drive it up my hilly driveway, back 
>> in the barh she goes.
>> (Sat am cold start, after warm-up rough idle and very low power,
>> stumblinjg)
>> 
>> Code is
>> 00537 VAG1551/2 Fault Code Number- See below C/O QW
>> 
>> After checking my records, I changed the easy stuff this morn.
>> new fuel filter
>> new Fuel regulator
>> New Oxygen sensor.
>> 
>> After each component change I cleared codes and ran again.
>> 00537 re-activates.
>> 
>> 
>> This brings me to the last one you guys may say is obvious, Fuel Pump.
>> I don't have records on this being changed..Hard to believe but..
>> 
>> 
>> QshipQ? , Dave Dawson? All takers?
>> 
>> Go ahead, beat me up for not changing the FP, but HELL! It's January in
> NH!
>> 
>> 
>> Jeff Posto
>> 
>> Oxygen Sensor Control Limit exceeded,
>> fuel pressure too low or too high,
>> intake or exhaust leak,
>> defective ignition system component,
>> intake air leak after air mass sensor,
>> O2 sensor is faulty
>> 
>> Symptom: CO before catalyst is below 0.3% or greater than 1.0%, 
>> Extremely lean or overly rich exhaust, Spark Plug foulin
>> 
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