Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Fuel Contamination
If an engine's fuel supply has been contaminated, the following procedure must be followed:
- Remove all fuel from fuel tank. Use an appropriate fuel container. Dispose of contaminated fuel through the proper procedure of disposal. Clean fuel tank. This will require removal of the fuel tank to make sure all contaminated fuel is removed. See REMOVAL .
- Install fuel tank to vehicle, see INSTALLATION .
- Fill fuel tank with fuel.
- Check for DTC's and clear DTC's.
- Start vehicle and run engine for 15 minutes and turn off vehicle.
- Check for DTC's and clear DTC's.
- Road test vehicle.
- Check for DTC's.
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 and or engine has been damaged are the following:
- Unstable fuel rail pressure. This can manifest itself as instability at idle speeds, excessive undershoot/overshoot at engine start, 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 inability of the fuel system to inject the proper amount of fuel.
NO RELATED
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.