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Engine performance (helpful tip)

Fellow Audi fanatics,
	Just recently I posted to the list about my engine problem (car was running 
rich and had no power and black smoke under boost).  I noticed that the 
frequency valve wasn't working, this led me to find that my computer had blown 
a transistor (it was easy to find the white transistor amongst all the black 
ones).  I ordered a replacement transistor and fixed the computer this past 
friday and adjusted the CO and the idle but later that night the valve quit 
working again.  I checked the computer again and the transistor was fine, the 
wires to the valve were fine.  Then I checked the computer outputs (fuse in 
fuel pump relay with key on) and the valve started working again.  I drove 
around the block and by the time I got back, the valve stopped working again.  
I shut the engine and was going to do an output test, I accidently moved the 
relay a bit and the valve started working again.  I touched the relay again 
and noticed that it was very hot compared to the others, so I pulled it out 
and openned it up to find that there were some cracked solder joints.  I 
resoldered the joints and put the relay back in and the car seems fine now (I 
guess it was the cracked solder connections which blew up the transistor in 
the computer).
	The moral of the story is that if any fellow fanatics are experiencing 
intermittent engine problems relating to the OXS frequency valve it might be a 
good idea to open up the fuel pump relay and have a look at the soldered 
connections or even purchase a new relay (I found that resoldering was a much 
cheaper solution).  The same may go for other relays causing intermittent 
	Just sharing how I solved my problem.
Audiman1@msn.com (Stefan Bendevis)
1987 5000 CD Quattro, lots of boost and no more black smoke: