Code 32, EGR System Error (All W/O 4L80-E Trans Except 3.1L, & 4.3L Turbo): Notes
ECM controls a solenoid that regulates vacuum to the EGR valve. The normally closed solenoid prevents vacuum from passing until it is energized by ECM. A properly operating EGR will directly affect fuel integrator counts. With EGR valve open, integrator counts will be less than without EGR operation. If monitored integrator counts do not change with EGR commanded, Code 32 will set.
ECM checks EGR operation when vehicle speed is greater than 50 MPH, engine vacuum indicates cruise and throttle is steady.
NOTE:
Test numbers refer to test numbers on diagnostic chart.
- With ignition on and engine off, solenoid should not be energized or allow vacuum to pass to EGR valve. When test terminal "B" of the ALDL connector is grounded, EGR solenoid should be energized, allowing vacuum to the EGR valve. Vacuum should hold.
- Checks for plugged EGR passages. If passages are plugged, engine may have severe detonation on acceleration.
- SERVICE ENGINE SOON light should also flash while diagnostic terminal is grounded. If it does not this may indicate the Quad-Driver has been damaged by low TCC circuit resistance.
- Vehicle must be driven during this test to produce sufficient load to operate EGR. Lightly accelerating (approximately 1/4 throttle) will produce a large and stable enough reading to determine if ECM is commanding system on.