'90 Cutlass Supreme 3100 PFI

[Matthew B. Watts]

-----Original Message-----
From: mccabet at mediaone.net <mccabet at mediaone.net>
To: diy_efi at efi332.eng.ohio-state.edu <diy_efi at efi332.eng.ohio-state.edu>
Date: Wednesday, February 25, 1998 12:46 AM
Subject: '90 Cutlass Supreme 3100 PFI


>I need some help diagnosing a problem with a '90 Cutlass Supreme with
>the 3100 PFi engine.  The scenerio goes like this:
>
>Engine starts and runs when cold.  It will re-start as long as you don't
>let it sit for a few minutes.
>
>Once it has sat, the engine will start and then promptly die.
>Depressing Gas pedal makes it worse (Dies quicker).
>
>Checked fuel pressure - 42PSI Key On Engine Running, 44 Key On Engine
>Off.
>
>Scantool shows no error codes in system.
>
>TPS checks good with no fluctuations noted.
>
>I know chrysler systems better than any other so I am lost on this one.
>A shop claimed the injectors was bad a quoted $1200 to fix.  I don't
>think it is injector related since the engine will start and run when
>cold.  By The Way, the engine will keep running and will even restart as
>long as you don't let it sit.


This is only a WAG but my '94 Dodge Ram started doing the same
thing just a week ago--right after it burned a whole in the exhaust
upstream of the cat-converter.  I'm guessing that air is getting into
the exhaust at idle and messing up the oxygen sensor once the
unit goes into closed loop mode.  I haven't began any repairs as
yet so I don't know if this is the real problem, but you may give it
at least 10 minutes of looking over before trying something
totally off-the-wall.

The good news is that my wife was driving it at the time when it
started sounding like a street-rod, so I'm off the hook regardless.  (-:

Hope this helps...

Matt Watts
University of Utah
Formula SAE Racing
_________________