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Home >> GMC >> 1998 >> Forward Control 7.4 B >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 7 (Engine Controls - Specifications - 6.5L Turbo Diesel) >> Fuel System >> Idle Speed
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Idle Speed

WARNING: This page is about a different variant/trim than selected.

Idle speed is adjustable on non-turbo only. Non-turbo engine uses mechanical fuel injection. All others use electronic fuel injection in which PCM controls all fuel delivery modes based on inputs from AAP, ECT and BARO sensors. Adjust idle speed on non-turbo engine by turning low idle speed screw on injection pump to curb idle speed specification shown on emission control information label.

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