I just got an 1989 audi 200 a couple days ago. I've been doing many repairs on this car to get it working right again. I let it warm up today for the first time and heard a screeching from the back of the engine when I revved it up above 1800rpm when letting off the gas the sound remained until it went to about 900rpms and the stopped. I tried removing my dipstick when it was making the noise with no change. I also put it in 1st and reverse gears with some load on to see if it went away. It seems to be too far back to be comming from any belts. I was thinking it might be distributor bearings. Any thoughts? Thanks

Pilot bearing in flywheel?

wouldn't putting the car in nuetral eliminate that?
I'm not ready to rip my trans off yet

Putting the car in neutral still allows the flywheel/pilot bearing to turn on the mainshaft.

could be a leaky rear main engine seal thats a little worn and dried out, the screeching could be air being forced through under load. Sometimes it goes away after being run on the road for a few minutes after the oil has been allowed to saturate the seal.
Alot of our older cars don't like to sit for long periods of time due to various older worn seals that dry out. HTH.

have a vacuum leak somewhere , not sure if it's related to your problem HTH

I'm thinking this may be it, when revving the engine up to about 3000rpm or so it starts to screech, and if i remove the oil cap the screeching stops, and the car dies. Maybe i'll try driving it around some to get some oil on that seal.

Oil cap should kill it.

Screeching from distributors is fairly common and running to get the oil going should help if that is it.

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