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Home >> GMC >> 1987 >> Forward Control 7.4 W, Standard >> Repair and Diagnosis >> Engine Performance >> System >> CCC Tests W/O Codes >> Rough, Unstable, Or Incorrect Idle, Stalling >> Symptom Definition

Symptom Definition

Engine runs unevenly at idle. If severe enough, vehicle may shake. Engine may display varied idle RPM ("hunting"). Either condition could be severe enough to cause stalling. Engine idles at incorrect speed.