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Chart C7 - EGR Check

The EGR valve is controlled by a normally closed solenoid (allows vacuum to pass when energized). The ECM energized solenoid to turn EGR on, and monitors EGR flow with EGR temperature switch. Code 32 will detect a faulty solenoid, temperature switch, or vacuum supply. CHART C7 checks for plugged EGR passages, a sticky EGR valve, or a stuck open solenoid. The ECM controls EGR based on engine coolant (about 77°F/25°C), throttle position sensor (off idle and steady), and MAP (steady throttle) inputs.

NOTE: The following step numbers refer to the numbers in the accompanying flow chart(s).
  1. With ignition on and engine stopped, solenoid should not be energized and vacuum should not pass to EGR valve.
  2. Grounding diagnostic terminal will energize solenoid and allow vacuum to pass to valve.
  3. Checks for plugged EGR passages. If passages are plugged, the engine may have severe detonation on acceleration.
Fig 1: Flow Chart C7, EGR Check
G4820
Fig 2: Flow Chart C7, EGR Check
GB0045424