DTC 32, EGR Circuit Error: Notes

WARNING: This page does not describe the selected car, but rather 10 other vehicles, including the 1995 GMC Yukon, 1995 GMC Suburban, 1995 GMC Pickup, 1995 GMC Cab & Chassis, and 1995 GMC C3500 HD. However, it is still accessible from the selected car via links, so may be relevant.

PCM operates normally-opened solenoid to control EGR valve. By providing a ground path, PCM energizes solenoid allowing vacuum to pass to EGR valve. During normal operation, PCM compares EGR duty cycle signal with EGR control pressure/BARO signal and makes adjustments in duty cycle accordingly. If there is a difference in PCM command and what is sensed by EGR control pressure/BARO sensor, PCM makes minor adjustments to correct. DTC 32 will set when:

RPM is greater than 506.
No DTC 31 or 33 is stored.
50 kPa difference between desired EGR and EGR pressure for 25.5 seconds.

PCM will default to shut down EGR.

NOTE: Test numbers refer to numbers on diagnostic chart.

This step determines if DTC 32 is result of a hard failure or an intermittent condition.
This step checks vacuum at EGR vent solenoid.
This step checks EGR valve.