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Home >> Chevrolet >> 2001 >> C3500 HD 6.5 F, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - 6.5L - Troubleshooting >> Excessive Smoke
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Excessive Smoke

Excessive Smoke

Checks Action
DEFINITION: White, black, gray or blue smoke under load, idle or start up hot or cold.
Preliminary Check
Fuel System Checks
Sensor Check
  • Check the engine coolant temperature (ECT) sensor. Use the scan tool in order to compare the engine coolant temperature with the ambient air temperature on a cold engine. If the coolant temperature reading is more than 5 degrees more or less than the ambient air temperature on a cold engine, check for a high resistance in the coolant sensor circuit or the coolant sensor.
  • Check the glow plug system operation. Refer to Glow Plug System Diagnosis .
Air Intake System Check
  • Check the air cleaner and the air intake ducts for restriction.
  • Check for a restriction in the turbocharger inlet duct.
  • Check for a restriction in the intake manifold.
Engine Mechanical Check
  • Check for incorrect basic engine parts such as the cam, the heads, the pistons, etc.
  • Check for excessive oil entering the combustion chamber.