With PFI

Code 32 Chart:

Code 32 Wiring Diagram:

CIRCUIT DESCRIPTION:

The ECM operates the vacuum solenoid to control the Exhaust Gas Recirculation (EGR) Valve. This solenoid is normally closed. By providing a ground path, the ECM energizes the solenoid, allowing vacuum to reach the EGR valve.

Under certain conditions, when the EGR valve is normally open, the ECM tests the EGR function by de-energizing the solenoid, blocking vacuum to the diaphragm. Without EGR, the system should sense a lean condition and increase the fuel integrator in response. The ECM monitors the amount of fuel delivery increase. If the increase is below a specified value, the ECM will interpret that the test was failed. The failure indicates that closing the EGR valve when it would normally be open does not make a significant change, indicating a problem in the EGR system.

NOTE: Because of all the possible color code combinations used on electrical wiring diagrams, always refer to ECM CONNECTOR IDENTIFICATION under ELECTRICAL AND ELECTRONIC WIRING DIAGRAMS for correct color code identification of circuit.



TEST DESCRIPTION: Numbers below refer to circled numbers on the diagnostic chart.

^ The diagnostic chart covers checks for the entire system. If no troubles found but code 32 was set, an intermittant electrical condition or a sticky EGR valve is at fault.




DIAGNOSTIC AIDS

^ The vacuum switch in the EGR assembly is not used.
^ An EGR valve stuck open will cause a rough idle.
^ A plugged or restricted solenoid vent could cause the EGR valve to remain open or close slowly.
^ An inoperative check valve in the ported vacuum line will result in faulty EGR operation.