What is causing a sporadic engine RPM surge without depressing the accelerator pedal on a 1999 Silverado 6.5L turbodiesel?
The problem has occurred at idle in park with no one in the vehicle; while in cruise control on the highway; after refueling and pulling out of a gas station and several other occasions while moving.
No DTC codes or freeze data was stored in the OBD. Approximately 2 yrs. Ago a new injector pump and PMD was installed by a GM dealership. The PMD was remoted from the pump. The problem is about a month old.
I removed the accelerator module and measured the resistances of the three potentiaometers supposedly contained in it but the values didn't make too much sense. I couldn't locate a spec sheet for the accelerator control module. Ever hear of such a problem?
Monday, January 10th, 2011 AT 6:18 PM