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Diagnostic Procedure (3.3L Models)

  1. Check exhaust system for leaks upstream from three-way catalyst, at manifold. If problem is found, repair as necessary. If problem is not found, warm to normal operating temperature. Disconnect vacuum hose from EGR valve. Check for vacuum at disconnected hose. Vacuum should not exist at idle. If using CONSULT-II, go to next step. If not using CONSULT-II, go to step  3 .
  2. Select EGRC SOLENOID VALVE in ACTIVE TEST mode with CONSULT-II. Turn EGRC solenoid valve ON. Check for vacuum at disconnected hose while revving engine from idle to 3000 RPM. Vacuum should exist. If operation is as specified, go to step  4 . If operation is not as specified, go to step  5 .
  3. Check for vacuum while revving engine from idle to 3000 RPM. Vacuum should exist. If vacuum is as specified, go to next step. If vacuum is not as specified, go to step  5 .
  4. Turn ignition off. Remove EGR valve. Using a hand vacuum pump, apply vacuum to EGR valve. EGR valve should open. Check EGR valve for sticking. If EGR valve is okay, go to step  12 . If EGR valve is not okay, clean or replace EGR valve as necessary.
  5. Inspect EGR valve vacuum hose for clogging, cracks or improper connection. If problem is found, repair as necessary. If problem is not found, using CONSULT-II, go to next step. If problem is not found, not using CONSULT-II, go to step  7 .
  6. Turn ignition on. Turn EGRC solenoid valve ON and OFF in ACTIVE TEST mode with CONSULT-II, and listen for operating sound. If operating sound is heard, go to step  8 . If operating sound is not heard, repair circuit or replace EGRC solenoid valve.
  7. Listen for operating sound while disconnecting and reconnecting EGRC solenoid valve harness connector. If operating sound is heard, go to step  9 . If operating sound is not heard, repair circuit or replace EGRC solenoid valve.
  8. Perform EGRC SOLENOID VALVE in ACTIVE TEST mode with CONSULT-II. Air should flow between ports "A" and "B". Air should not flow between ports "A" and "C". Remove jumper wires. Air should not flow between ports "A" and "B". Air should flow between ports "A" and "C". EGRC solenoid valve should switch in one second or less. If operation is as specified, go to step  10 . If operation is not as specified, replace EGRC solenoid valve.
  9. Turn ignition off. Remove EGRC solenoid valve. See Figure . Using jumper wires, apply battery voltage between EGRC solenoid valve terminals. See Figure . Air should flow between ports "A" and "B". Air should not flow between ports "A" and "C". Remove jumper wires. Air should not flow between ports "A" and "B". Air should flow between ports "A" and "C". EGRC solenoid valve should switch in one second or less. If operation is as specified, go to next step. If operation is not as specified, replace EGRC solenoid valve.
  10. Remove EGRC-BPT valve. Plug one vacuum port and apply vacuum to other vacuum port, located on top of valve. Vacuum should not hold. Apply about 3.94 in. H2 O (1.0 kg/cm2 ) of vacuum to backpressure port. Vacuum should hold. If operation is as specified, go to next step. If operation is not as specified, replace EGRC-BPT valve.
  11. Remove EGR temperature sensor located near EGR valve. Place sensor in heated water. Measure resistance between EGR temperature sensor terminals, with water at specified temperatures. See EGR TEMPERATURE SENSOR RESISTANCE  table. If resistance is as specified, go to next step. If resistance is not as specified, replace EGR temperature sensor.
  12. No problem is indicated at this time. Problem may be intermittent. See INTERMITTENTS in TROUBLE SHOOTING - NO CODES article.
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