What would cause my 1999 Chevy Tahoe to idle too high? It will eventually return to idle speed about 20 seconds after you get stopped but makes stopping at red lights difficult. On the highway, it never returns to idle speed which causes you to have to ride the brakes more than needed. When you stop and put the vehicle in park, the idle speed goes up to about 1500 rpms for a few seconds and then drops down to about 900 rpms like it should. However , when driving , it seems like it is always trying to run at 1500 rpms most of the time. If you coast for miles, then it will every once in a while drop back to idle speed.
Jan 9, 2010 at 9:11 AM