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Fuel Contamination






FUEL CONTAMINATION

If a diesel engine's fuel supply has been contaminated (with gasoline, water, etc.), the following procedure must be followed:

1. Remove all fuel from the fuel tank. Use an appropriate fuel container. Dispose of the contaminated fuel using the proper procedures.

CAUTION: Dispose of petroleum based products in a manner consistent with all applicable Local, State, Federal, and Provincial regulations.

2. Remove and clean fuel tank.
3. Install the fuel tank.
4. Fill fuel tank with fresh diesel fuel.
5. Drain and remove the fuel filter.
6. Install a new fuel filter.
7. Check the engine control module for any diagnostic trouble codes (DTCs). Record and clear any DTCs that are present.
8. Start and run the engine. Run the engine for up to 15 minutes to allow time for any DTCs to reset and shut off the engine.
9. Check the engine control module for any diagnostic trouble codes (DTCs). Record any DTCs that are present. Refer to the appropriate engine electrical diagnostics to diagnose any DTCs that were set.

CAUTION: With the high pressure fuel system in this vehicle, any residual contaminated fuel will be removed very quickly. Shut off the engine immediately if signs of engine damage are noted.

The engine should then be evaluated to determine if the contaminated fuel has caused any damage to the fuel system and/or engine. Indicators that the fuel system has been damaged include the following:

- Unstable fuel rail pressure. This can manifest itself as instability of idle speeds, excessive undershoot/overshoot at engine start-up, or excessive undershoot/overshoot when the engine operating conditions change. A typical engine response to a large rail pressure undershoot would be a decrease in engine speed or engine stall.
- Excessive noise from the engine. This could indicate poor rail pressure control or the inability of the injection system to inject the proper amount of fuel.
- Excessive smoke (black or white). This could indicate the inability of the fuel system to inject the proper amount of fuel.

NOTE: If any of these conditions are exhibited after cleaning the fuel system, proceed to the appropriate engine electrical diagnostic information. Repair the fuel system and/or engine as necessary.