91 100 CIS-E III NF..stalling hot

[John Gourley]

*91 100 FWD NF engine with CIS-E III stalls at times when hot, especially
when 100 degrees or higher ambient temp*.* won't restart until cooled down*
.............*full post at bottom of this message*


Have you tried plumbing in a fuel pressure gauge positioned where you can
see it from the driver's seat? That and a test light wired in parallel to
the pump should tell you whether you've got a fuel pressure problem, and if
so, whether it's the pump, or the power supply to the pump.

Joshua

===========================================

Sounds like an engine speed sensor.  Gets hot and fails to provide a good
signal to the ECU that allows the rest of the ignition system to work.

Kneale

=================

Thanks for the ideas...................installing a fuel pressure gauge that
I can watch while driving has been on my mind, and will probably end up
doing just that.  At least would let me know if it is fuel shutting down
that causes the problem


I've been reading with interest the ongoing talk about speed sensors getting
hot and causing problems............ My 2.3 NF engine doesn't have those
sensors


thanks again

John Gourley

=================================================================

*original full post*

For anyone that has or has had a 91 100  Audi with CSI-E III NF
engine..........been fighting a problem with the wife's 91 100 FWD.  When
the ambient temp gets to 98-100 degrees or more, the problem can happen.  I
take a 50 mile drive on the freeway to Tucson,AZ....runs fine...then during
the course of stop and go driving around Tucson, it sometimes acts up.  I
get a slight two or three jerks and the engine shuts down.  Jerks might be
too strong a description, the passenger won't even feel it.  Feels like the
fuel is shutting down.  So I sit parked on the side of the road for maybe 15
minutes.........then starts right up and may run fine for another 20 minutes
of stop and go driving then shuts down again.  Yesterday was about 100
degrees in Tucson...it happened.  So we found a restaurant, had a long lunch
and one hour later took off fine.  Drove 10-15 miles of stop and go driving,
got onto the freeway and headed the 50 miles home.  It ran fine.  The longer
I let it cool down the more miles I can probably drive before shutting down
again

Something is warming up and shutting off, causing the problem AND if ambient
stays under 95 degrees there is no problem.  Seems to take a combination of
an hour or so of highway driving and then city stop and go.

Has anyone ever had the fuel distributor cause such a shutting down
problem.  I know a dirty or otherwise bad fuel distributor can certainly
make for poor running...but can it actually shut down an engine?   I've
never seen that happen but I haven't seen it all!

I mention the fuel distributor because most other parts are new.  New fuel
pump, new pump check valve, new accumulator, new fuel pressure regulator,
new injectors, new temp sensors (both of them) new oxy sensor, new fuel pump
relay, new cold start valve