Subject: Re: '91 200q 20v stalls after acceleration & then clutch

[JKB944T@aol.com]

I experienced this same exact problem several months ago.  I was told that it
was an oxygen sensor or idle stabilizer by Blaufergnugen so I replace both
but still had the problem.  I finally figured out on my own that I had a bad
turbo bypass valve which is p/n 034-145-710-A and costs only 55 dollars.
 This simple valve sovled the problem.  The valve is quit simple to test.  

To Test Valve.
Simply depress the plunger, then place finger over the small vacuum line
orfice.  Then let go of the plunger.  If the plunger springs back then the
valve is defective.  If the plunger stays back when you let go of it then
your problem may be in the vacuum line feeding the valve.

Good Luck,
Jeff Bernstein