Diagnostic Aids
WARNING: This page is about a different car, the 2002 Pontiac Grand Am, 2002 Oldsmobile Alero, 2002 Chevrolet Monte Carlo, and 2002 Chevrolet Impala. However, it is still accessible from the selected car via links, so may be relevant.
Check for excessive deposits on the EGR pintle or seat. Remove the EGR valve and inspect for deposits that may interfere with the EGR valve pintle extending completely or cause the pintle to stick. If problem is intermittent, refer to INTERMITTENT CONDITIONS under SELF-DIAGNOSTIC SYSTEM.