Idle Speed & Ignition Timing
WARNING: This page is about a different car, the 2003 Pontiac Aztek and 2003 Buick Rendezvous. However, it is still accessible from the selected car via links, so may be relevant.
Idle speed and ignition timing are controlled by PCM. Incorrect idle speed are normally caused by dirty throttle plate or vacuum leaks. Ensure all vacuum components are functioning properly.