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HOMESERVICE MANUALSCHEVROLET1995SPORTVAN G20, 6.5 PREPAIR AND DIAGNOSISENGINE PERFORMANCETESTING & DIAGNOSISENGINE CONTROLS - TESTS W/CODES - 4.3LTROUBLE CODE CHARTSCODE P0400, EGR ERROR - "S" & "T" SERIES 4.3L (VIN Z)NOTES
1995 Chevrolet Sportvan G20, 6.5 P

Code P0400, EGR Error - "S" & "T" Series 4.3L (VIN Z): Notes

1995 Chevrolet Sportvan G20, 6.5 PSECTION Notes

Control module operates an EVRV solenoid, that is pulse width modulated to control EGR valve. Solenoid is normally closed. By providing a ground path, control module energizes solenoid which allows vacuum to pass to EGR valve. Control module can vary solenoid on time from zero to 100% depending on load conditions.

Control module monitors EGR effectiveness by de-energizing EGR control solenoid, thereby shutting off vacuum to EGR diaphragm. With EGR valve closed and oxygen sensor operating normally, short fuel trim count will be greater than during normal EGR operation. If test passed, it will be run only once during ignition cycle. If test failed, it must fail twice before Code P0400 will be set.

NOTE: Test numbers refer to numbers on diagnostic chart.
  1. With ignition on and engine stopped, solenoid should not be energized and vacuum should not pass to EGR valve. Grounding diagnostic terminal will energize solenoid and allow vacuum to pass.
  2. Checks for plugged EGR passages. If passages are plugged, engine may have severe detonation on acceleration.
  3. MIL should flash while diagnostic terminal is grounded. If light does not flash, it may indicate that quad-driver module has been damaged.
  4. Vehicle must be driven during this test to ensure sufficient load to operate EGR.
RENDER: 1.0x

NO RELATED

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