I have a 95 Riviera with about 93K mileson it. About 5-10secs after turning the car off a noise like a motorrunning begins and usually continues on and off for as much as a half an hour.


I've looked under the hood and there doesn't seem to be anything on in or around the engine. It seems as though the noise is comming from the rear of the car!?!?! Almost in the rear fender area?


Does anyone have any idea what this could be???


Ive searched all over a bunch of forums and can't find anything like this


Thanks for the help

 

I've heard that sound before on a friends Cadillac, I believe that is the rear suspention adjusting itself, but why is it doing that? Probably have a air leak in the system somewhere back there.

 

I was thinking fuel pump but really have no idea

 

It's your air compressor pumping air into the rear airshocks to level the car. My Riviera did that, too until the compressor failed. either you have an air leak, or the level switch is out of adjustment.