Pontiac Repair: 1999 Pontiac Gran Prix, pontiac gran prix, throttle position sensor

Question
I turn on the engine and the transmission races.  If I turn the car off and on a few times, it finally begins to idle smoothly.  If I let it race and begin to drive, the car will speed up on its own.

Answer
Hi Becky:

what enegine is in this?
My first though is a vacuum leak someehere and that is causing the issue. This is a safety issue I would get it looks at righ taway it may decide to race fast enough at the wrong time that you can't catch it and stop from hitting something.. My second guess would be an idle control motor that's hanging up or sticking.. My last though would be a throttle position sensor that's not reading wight when the gas pedal is released and that is making the idle speed rise.
Good luck :)