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Home >> GMC >> 1996 >> Forward Control 4.3 W >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Tests W/O Codes - Diesel >> Symptoms >> Low Engine Power
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Low Engine Power

SYMPTOM - LOW ENGINE POWER

Possible Cause Correction
Restricted air intake Remove restrictions
Plugged fuel filter Remove restriction and/or replace filter
Faulty PCM operation See TESTS W/CODES article
Improper fuel return system Check fuel return system
Restricted tank-to-pump fuel supply Check fuel delivery system
Incorrect or contaminated fuel Remove and replace fuel
Faulty EGR operation Check EGR system
Worn camshaft or valves Repair as necessary Check compression and valve lift
Nozzle or glow plug compression leaks Check fittings, and replace as required
Plugged nozzle Remove restriction and/or replace nozzle
Worn or damaged turbocharger turbine wheel, shaft or compressor wheel (if equipped) Repair or replace turbocharger assembly
Faulty TCC or shift points Check transmission operation