Circuit Description

WARNING: This page is about a different car, the 2000 Pontiac Firebird, 2000 Chevrolet Corvette, and 2000 Chevrolet Camaro. However, it is still accessible from the selected car via links, so may be relevant.

This test checks if EGR valve is stuck open. PCM determines that EGR is stuck open if actual EGR position and learned closed EGR position vary by greater than a predetermined value. PCM checks for a stuck valve when desired EGR position is at zero percent. PCM commands EGR valve to 100 percent during certain driving conditions in order to clear a possible restriction from EGR valve if PCM determines that valve is stuck open.

PCM rechecks for a stuck valve when desired EGR position returns to zero percent. A failure timer increments if the stuck EGR valve condition is still present. This DTC sets when timer reaches a predetermined value and ignition voltage greater than 11.7 volts and actual EGR pintle position greater than 0.29 volt when valve is commanded closed.