Re: 91 200TQ Stalling

[Peter Henriksen <peterhe@Microsoft.com>]

It's not the exact same steps to reproduce, but my 20v 200q did the same
thing for a long time when coasting to a stop in neutral or with the clutch
in. 
Ned Ritchie of Intended Acceleration mentioned that he's had 2 other people
with 91 200qs with the same problem and had them replace the turbo bypass
valve. Turns out that if said valve is not working correctly, the engine
will use the intercooler as a reservoir for air, thus not drawing any fresh
air through the intake. This makes the air mass sensor report to the ECU
that there's air being taken in, and the ECU shuts off the fuel because "the
engine is obviously not running." Well, not anymore, it ain't.
I don't know if this is your problem, but it can't hurt to try.

- peter, peterhe@microsoft.com, http://www.geocities.com/motorcity/1001
  98 volvo v70 t5 - 5-speed
  94 acura legend gs - 6-speed!

------------------------------
Date: Wed, 1 Apr 1998 15:31:06 -0800
From: rmurphy@batnet.com (Oscar Murphy)
Subject: 91 200TQ Stalling

QListers,

We have a nagging problem with our 1991 200 TQ (20v) sedan. To date it has
perplexed 2 dealers and 1 independent mechanic. The car has 98K miles on
it.
We've owned it since new and have had all regularly scheduled maintenance
performed at the local dealer.

SYMPTOM:
Car stalls on when shifting @ 3000 rpm after hard acceleration. If I shift
at a higher or lower engine speed the problem doesn't occur. If I
accelerate normally, it doesn't ocur.

I have noticed that as I pass through neutral when I shift @ 3000 rpm after
hard acceleration, the tach needle drops to 0 rpm and the car stalls.

Under other shifting conditions, the tach needle drops to ~500 rpm and then
bounces up to ~800rpm as I pass through neutral.

ATTEMPTED FIXES:
1) Engine speed sensor replaced
2) Injectors cleaned, later replaced
3) Throttle position sensor replaced
4) Breather hose and vacuum  hoses replaced

No new diagnostic failures reported on computer readouts after the engine
speed sensor was replaced. Various electrical tests performed per Audi
repair procedures check out within tolerances.

As you can probably tell, I'm not a mechanic so I may not have given enough
info here. Any help would be greatly appreciated.

Regards,
Oscar