[s-cars] Re; not the code I expected

[smarinello at entouch.net]

Tom,

The CEL came on briefly a couple of hours before the first no start occurrence.  
Other than that, the car have been running relatively well, a bit smoother with the 
new injectors, and not exhibiting any characteristics that would make you think the 
pump was having problems.  It has not been driven particularly hard lately, in large 
part because the timing belt should probably be replaced by both miles and time, 
although it looks good and does not appear to be loose at all.  The only running 
issue is the one that precipitated the upgrade/replacement of the cats with a new O2 
sensor and new plugs in the Spring and the new injectors recently; that being that 
the mileage ain't what it should be. It smells rich at times.  There have been 
occasions that there is erratic ideally at a stop, making me think a vacuum leak is 
playing in all of this, but when I have started it up and want to check, it doesn't 
do it and I can't find anything...although I do not profess to be as adept at that 
with the S-car.  I'm still stuck in the urq mode...and I've forgotten most of that.

I can't see how any of this stuff would cause a no start situation, however.  Bad 
running, but not no start.  There was a second occurrence two days ago when my wife 
stopped for gas (yes, our cars get passed around relatively unimpeded) after going 
shopping.  She called my son to come help her push it to the side, but when he got 
there, it just fired up. SO it's a warm/hot situation, but it doesn't necessarily 
take too long to cool down enough.

Ben has suggested checking the timing belt alignment, which I will, although it 
would be hard to imagine it slipping with it as tight as it seems to be.  On the 
other hand, I better look a little closer...maybe it's tight because it's running on 
top of the gear teeth and not slotted in correctly.  I will probably have to take it 
to a mechanic to get the VAGCOM  to pull codes...or maybe I should just bite the 
bullet and get it for myself now.  What's the going rate and what would I need?  
Hell, I've already put so much new into this thing, what's little more? ...and it 
still needs the headlight switch replaced (got that) the bent strut tower replaced 
and the t-belt, so I'll have to keep it a couple of years anyway.

Steve

On Thu Sep 24 12:06 , Tom Green  sent:

>There is a lot of information about O2 sensor codes in the Bentley and
>many troubleshooting tips.  It is important to understand that most  
>codes
>are not a direct indication of the sensor condition but a secondary  
>result of
>some other problem.  Anything that causes excessive or insufficient  
>amounts
>of fuel in the system will exceed the limits of the O2 sensor  
>adjustment and
>should result in a code and MIL.
>
>And, no, the O2 sensor will not prevent the engine from starting.
>
>At the point that the engine does not start, if it is a faulty CPS, it  
>is not
>intermittent at that point.  If the MIL was on when you shut down (and  
>it was
>caused by an open or short in the CPS) you would expect a code.
>
>I am not sure about the blink codes coverage, but it's better than  
>nothing.
>The VAG-COM will give you more information about the fault.  Right now
>you don't know if the fault is rich or lean.  Bentley also indicates  
>the MIL
>will be on when this DTC is present.  Is there a VAG-COM available in
>your neighborhood?  Have you observed the MIL on when driving the car?
>
>Because the symptoms closely match the CPS failure syndrome experienced
>by so many listers, you may have started down this path to the  
>exclusion of
>of other possible causes that do not have a specific DTC, i.e., fuel  
>pressure
>or supply.  Perhaps you have had some clues, i.e., poor mileage that  
>have
>not been resolved?  I did not understand your other comments about ....
>overheating and other assorted comments in the Bentley??
>
>You can verify if a CPS fault will record a code by unplugging the  
>sensor at
>the front of the fuel rail while the engine is running and then  
>plugging it back
>in.  That might eliminate a little guessing even if it is not totally  
>conclusive.
>
>Tom
>
>> -----Original Message-----
>> Date: Wed, 23 Sep 2009 23:09:45 -0500
>> From: "Steve Marinello" smarinello at entouch.net>
>> Subject: [s-cars] not the code I expected
>> To: "'S-Cars'" s-car-list at audifans.com>
>> Message-ID: 8613DE88AA7A4D0AB99112860184A19B at GT5674>
>> Content-Type: text/plain;	charset="us-ascii"
>>
>> Well, the S6 has failed to start one more time.  It was warm.  It  
>> restarted
>> after it cooled off a bit.
>>
>> Finally blinked the codes, expecting the cam sensor, if anything.   
>> NOT.  Got
>> 2341; oxygen sensor..overheating and other assorted comments in the  
>> Bentley.
>>
>> There was a new sensor put on in the Spring, along with two new  
>> cats.  As
>> you may remember, I was frustrated that the sensor was bad, because  
>> the
>> mileage did not improve and, in fact, got worse.  My mechanic  
>> checked the
>> sensor and said it was functioning fine.   Hmmm.
>>
>> Would the O2 sensor even keep it from starting?  Which way to go  
>> now?  I
>> suppose the first step is to check the current CPS and see if it is
>> functioning, but since it's intermittent even when hot, that may not  
>> show
>> anything.
>>
>> Let me know what you think.
>>
>> TIA,
>> Steve
>