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Home >> GMC >> 1990 >> Forward Control 3.9 L >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Tests W/O Codes >> Symptoms (Diesel) >> Engine Will Not Idle
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Engine Will Not Idle

ENGINE WILL NOT IDLE

Possible Cause Correction
Linkage binding or misadjusted Remove binding and readjust linkage
Restricted Air Filter Check and/or replace air filter
Defective injection pump Replace injection pump, see SYSTEM/COMP TESTS
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