GM Code 32 EGR System
CODE 32 - EGR System
Trouble Code 32 indicates that the Exhaust Gas Recirculation (EGR) valve diaphragm is not where the ECM expects it to be. The ECM controls the diaphragm with a Pulse-Width Modulated (PWM) waveform. The EGR has a vacuum bleed solenoid that adjusts the vacuum applied to the EGR valve based on this pulse width. If there is sufficient vacuum at the EGR valve, a switch closes to send a signal back to the ECM. The absence of this signal is the bases for code 32.
The conditions for setting this code are:
- no vacuum to EGR (switch open), and
- Code 33 or 34 (MAF error) is not present, and
- engine running and LV8 is less than 100, and
- coolant temperature is > 118 deg F (48 deg C), and
- the EGR solenoid duty cycle is < 65%, and
- the above conditions are met for more than 25 seconds
Typical causes for this code include:
1) Faulty EGR valve-to-ECM connection
2) Plugged EGR passages and/or sticking EGR valve
3) Defective EGR valve
4) Defective ECM
