G 3500 1 Ton Van V8-454 7.4L VIN N TBI (1995)
EGR Valve: Testing and Inspection
RESULTS OF INCORRECT OPERATION
With too much EGR flow at idle, cruise, or cold operation, any of the following conditions may occur:
-
Engine stops after cold start.
-
Engine stops at idle after deceleration.
-
Vehicle surges during cruise.
-
Rough idle.
If the EGR valve should stay open all of the time, the engine may not idle.
-
DTC 32 may set.
Too little or no EGR flow allows combustion temperatures to get too high during acceleration and load conditions. This could cause:
-
Spark knock (detonation).
-
Engine overheating.
SYSTEM CHECK
Diagnosis of the EGR system is covered in Computers and Control Systems / System Diagnosis / C Charts. See: Computers and Control
Systems/Testing and Inspection