[s-cars] Car bucking under WOT - I have codes

[Andrew Lee Jackson]

Hey Scott,

I too experienced the "buck" about two weeks ago.

This was after reconnecting the negative terminal on the battery and
taking her for a semi-spirited drive.
The bucking was very similar to what you described except that it
happened to me at only 3/4 throttle.
I didn't bother dumping the codes because I figured that it was just the
ECU hiccuping as it still had some learning to do.

The motor was just nearing the end of it's "break-in" so I just kept the
throttle below 1/2 for another week or so.

Interestingly enough though, (especially now after reading your post,) I
discovered shortly thereafter that my IAT sensor was blown to bits.

http://pictureposter.audiworld.com/24811/p0006140.jpg   <-(WTF happened
here??!)

I have since replaced the sensor, and have not experienced any bucking,
even at WOT.
Could just be coincidence though.


Hope this gives you some direction.

ALJ

-----Original Message-----
From: s-car-list-admin at audifans.com
[mailto:s-car-list-admin at audifans.com] On Behalf Of Scott Munger
Sent: November 12, 2002 7:47 PM
To: s-car-list at audifans.com
Subject: [s-cars] Car bucking under WOT - I have codes


Listers,
Thank you respondants for all your help and BTDT, I greatly appreciate
it. I ran the CEL codes and got the following (2 corroborate with other
listers).  Thanks to http://www.sjmautotechnik.com/20vcodes.htm for the
decoding:

2322
Inlet air temp
Open or short circuit
Defective sensor or wiring
Symptom: Slight power loss, Increase in fuel consumption

2222
Pressure sensor
ECU Pressure sensor defective,
Repair or replace ECU

2224
Over boost condition
Waste gate or pressure hose, Waste Gate Solenoid/hose problem

2413
Mixture Adjustment,
Adaptation limit exceeded,
Symptom: Rich mixture, increased fuel consumption


All of these sound pretty bad, but I'm very glad they confirm my initial
estimates and match up w/others experience.

I've got quite a bit more debugging to do, I'm resetting the ECU and
will run the drive test again to make sure I didn't miss any codes.

Has anyone had these codes all together?  Could a bad pressure
transducer in the ECU cause all of these problems?  Or is the 2222
likely to be in reaction to a problem with the boost plumbing?


--Scott Munger
'93 S4


> -----Original Message-----
> From: s-car-list-admin at audifans.com
> [mailto:s-car-list-admin at audifans.com]On Behalf Of Scott Munger
> Sent: Tuesday, November 12, 2002 7:26 AM
> To: s-car-list at audifans.com
> Subject: RE: [s-cars] Please Help - Car bucking under WOT
>
>
>
> (No ECU mods - stock + exhaust + air filter is all)
> I'll need to dig deeper and do some troubleshooting, but several have
> suggested the MAF, even some 1.8t'ers. Thanks for the feedback.
>
> --Scott Munger
> '93 S4
>
>
> > -----Original Message-----
> > From: CaptMagu at aol.com [mailto:CaptMagu at aol.com]
> > Sent: Monday, November 11, 2002 11:25 PM
> > To: mungerts at uneedspeed.net; s-car-list at audifans.com
> > Subject: Re: [s-cars] Please Help - Car bucking under WOT
> >
> >
> > Scott
> >
> > Sounds like you ran into the infamous max MAF flow ECU cut. A quick
> > reset can be had by turning the ignition off then on. The lower
> > altitude(4000ft vs home
> > might have got you). Beware of the steering wheel lock if you
> > try to remove
> > your key at speed. You might try a total reset of the ECU to
> > get your lost
> > boost back. You didn't mention what engine/ECU mods you have.
> >
> > Hap, chillin' on Anini Beach, Maguire
> >
>
>
> _______________________________________________
> S-CAR-List mailing list
> S-CAR-List at audifans.com
> http://www.audifans.com/mailman/listinfo/s-car-list
>


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