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 System Cleaning
Special Tools
- J 34730-1A Fuel Pressure Gauge
- J 37088-A Fuel Line Disconnect Tool Set
- Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection (LS7 or LS9) , Battery Negative Cable Disconnection and Connection (LS3) .
- Relieve the fuel system pressure. Refer to the Fuel Pressure Relief (Without CH 48027) , Fuel Pressure Relief (CH 48027) .
- Drain the fuel tanks. Refer to Fuel Tank Draining .
- Remove the fuel tanks.
- For the left fuel tank, refer to Fuel Tank Replacement - Left Side .
- For the right fuel tank, refer to Fuel Tank Replacement - Right Side .
- Remove the fuel sender assemblies.
- Inspect the left fuel sender strainer. Replace a contaminated strainer for the left fuel sender only, and inspect the fuel pump.
- Inspect the left fuel sender fuel pump inlet for debris. Replace the left fuel sender assembly if you find debris in the fuel pump inlet.
- Inspect the right fuel sender strainers. Replace the right fuel sender assembly if you find a contaminated strainer. The right fuel sender strainers are not serviced separately.
- Flush the fuel tanks with hot water.
- Pour the water out of the fuel sender assembly openings. Rock the tanks to be sure that removal of the water from the tanks is complete.
- Install the fuel sender assemblies.
- Install the fuel tanks.
- For the left fuel tank, refer to Fuel Tank Replacement - Left Side .
- For the right fuel tank, refer to Fuel Tank Replacement - Right Side .
- Refill the fuel system.
- Install the fuel filler cap.
- Connect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection (LS7 or LS9) , Battery Negative Cable Disconnection and Connection (LS3) .
- Perform the following procedure in order to inspect for leaks:
- Turn the ignition switch ON for 2 seconds.
- Turn the ignition switch OFF for 10 seconds.
- Turn the ignition switch ON.
- Inspect for fuel leaks.
- Program the transmitters. Refer to Remote Control Door Lock and Theft Deterrent Transmitter Programming (without XL8 or Z49) , Remote Control Door Lock and Theft Deterrent Transmitter Programming (with XL8 or Z49) , Remote Control Door Lock and Theft Deterrent Transmitter Programming (New RCDLR ONLY) .
Refer to Battery Disconnect Warning .
When flushing the fuel tanks, handle the fuel and water mixture as a hazardous material. Handle the fuel and water mixture in accordance with all applicable local, state, and federal laws and regulations.
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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.
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