I have a 2000 Saturn SL1. The engine races when I turn on the ignition. The racing does not die down after a warmup period. The car will drive along at 20-30 mph without putting my foot on the gas pedal. What can I do to address this problem? It is eating up my gas mileage.
Clean throttle body, if it is gumed up it could keep throttle from closeing all the way.
Search will tell you how to do it
Look for a stuck throttle plate, throttle cable, or anything that is holding the throttle plate open. Also check for a vacuum leak such as a vacuum hose pulled loose or a vacuum device that is hissing loudly. Somehow, too much air is getting into the intake.
Hope that helps.
Do the stuff suggested, but first see if there are any stored codes. The throttle position sensor, the mass airflow sensor, the manifold absolute pressure sensor, perhaps even the temp sensor could be the cause. Any of these can cause a faulty idle and many will store a code.