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Code 32, EGR System Error

EGR vacuum is regulated by an ECM-controlled solenoid. The ECM will turn the EGR on and off (duty cycle) by grounding and removing ground to circuit No. 435. The duty cycle is calculated by the ECM based on coolant temperature, airflow and engine RPM. There should be no EGR under the following conditions:

With the ignition on and engine stopped, the EGR solenoid is de-energized. By grounding the ALDL test terminal, the solenoid should energize.

NOTE: Test numbers refer to test numbers on diagnostic chart.
  1. Grounding the ALDL test terminal should cause the EGR solenoid to close, allowing vacuum to be applied. Vacuum should hold.
  2. Determines if the electrical control part of the system is at fault or if the connector or solenoid are at fault.
  3. By plugging the EGR valve side and removing ground from the ALDL test terminal, solenoid valve should open and allow vacuum to bleed off through vent.
  4. With the engine not running and vacuum applied to valve, valve should move to the fully open position.
  5. System uses negative backpressure to open EGR valve. Valve should close when the engine is cranked.
Fig 1: Code 32, Schematic, EGR System Error
G91D07418
Fig 2: Code 32, Flow Chart, EGR System Error
GB0021395