I have a 1990 525i and recently when i have been driving it the throttle will get stuck at a certain rpm.

For example, I will be driving in 3rd and i will rev it up to 3 thousand rpm and even when i take off of the gas it will just stick there until i shift it into 4th and then in fourth it will repeat.

When i stop and park, or sit at a stop light, my rpm will raise up to 35 hundred or so and just stay there until i shift it into gear. I have looked under my hood as it is self accelerated to 35 hundred, and the physical throttle cable is fully closed or pulled back. So the gas pedal isnt physically stuck or anything.

Sometimes if i shut my car off and let it sit for a bit and then start it back up again then it will run normal. But it has been doing this more and more frequently lately.

I am pretty new when it comes to working on bmw's so i have no idea what this could be. If any of you guys could help i would really appreciate it.

It sounds like you may have a sticking throttle cable. In which case replacement of same is indicated.

I don't think that is it because the throttle cable is all the way back when it is "stuck" accelerated.

I would check the throttle body of the car while it is idling and the problem is occuring. It may have something to do with an idle air control or a vacuum leak.

I don't think that is it because the throttle cable is all the way back when it is "stuck" accelerated.
When it is in that condition can you twist the throttle plate closed and bring down the engine speed?

Idle air valve sticking? easy thing is take it off and clean it.

the throttle plate is fully closed when this is happening.

I do not believe that it is just something sticking because it will actually accelerate on its own. When i first start it up it will accelerate to about 35 hundred rpm and idle there... or if i shift into a higher gear the rpms will go down momentarily but my car will actually slowly accelerate on its own back up to 35 hundred...

Is it possible that it is an air leak from a cracked or worn out intake or vacuum hose?

If so i will replace a few and see if that helps.. I noticed some are in pretty bad shape