1981 528i - I was driving the other day and put the throttle to the floor. The transmission kicked down and the engine speed increased. When I let off the throttle the engine speed stayed hgih. I put the car in neutral and the RPM was around 3600. I put the car back in gear and drove home. The throttle linkage in not stuck, but I can not get the idle to come down. Any thoughts? Thanks, Jeff