Probable Causes
- Fuel Ratio Control setting
- Fuel injection timing
- Faulty unit injector
- Air inlet restriction or air inlet leak
- Exhaust restriction or exhaust leak
- Faulty turbocharger
Recommended Repairs
Fuel Ratio Control Setting
If excessive black smoke appears during acceleration only, check the Fuel Ratio Control setting. If the Fuel Ratio Control is adjusted too rich black smoke during acceleration can occur. Refer to Troubleshooting, "Fuel Ratio Control".
Incorrect Fuel Injection Timing
Check the fuel injection timing. Ensure that the fuel injection timing is adjusted correctly. Refer to the Systems Operation, Testing And Adjusting module.
Faulty Unit Injector
Faulty unit injectors will normally cause the engine to misfire which will cause the engine to run rough. Faulty unit injectors can also cause too much smoke even if the engine is running smoothly. Remove the unit injectors and check the unit injectors. Use the 1U-6661 Pop Tester Group to check the injectors for proper operation. Refer to Special Instruction, SEHS8867 for additional information.
Air Inlet Restriction or Air Inlet Leak
Check the air inlet for restrictions. Also check the air inlet for air leaks.
Exhaust Restriction or Exhaust Leak
Check the exhaust system for restrictions. Also check the exhaust system for exhaust leaks.
Faulty Turbocharger
Check the inlet manifold for oil. If oil is present in the inlet manifold, repair the turbocharger.