Fuel System Cleaning Procedures

WARNING: Locate class B fire extinguisher to work area.

After it is determined that the fuel system is contaminated, the following procedure to clean it is recommended;


1. Place vehicle on hoist and open hood.

WARNING: Do not allow smoking or the use of open flames in the area where work on the fuel system is taking place. Any time the fuel system is being worked on, disconnect the negative battery cable, except for those tests where battery voltage is required.

2. Disconnect negative battery cable at battery and remove fuel fill cap.
3. Raise vehicle to a comfortable working position.
4. Drain fuel tank.
5. Remove fuel filter.

Fuel Tank Filler Connections:

6. Remove fuel tank.

Fuel Line Connections At Engine Compartment:

7. Disconnect fuel lines at engine.
8. With compressed air, blow out supply and return lines. Catch fuel in a container at opposite end of lines.
9. Replace fuel filter and connect lines at engine.

Lifting Fuel Pump Module:

10. Remove pump module.
11. Inspect strainer on pump; replace if plugged or damaged.
12. Flush tank with hot water for at least six minutes; invert and drain. All metal chips/debris must be removed from the tank prior to installation.

Module Return Line:

13. Using maximum air pressure of 69-103 kPa (10-15 psi), blow air in the pump module return line.

Fuel Supply Line:

14. Disconnect fuel supply to filter at front of vehicle. Connect a hose to fuel supply pipe and insert other end of hose into an empty one gallon fuel can.
15. Connect battery cable.

IPJB - Instrument Panel Junction Block:

16. Put six gallons of clean fuel into fuel tank and apply 12 volts to interior fuse panel fuel pump test hole or turn the ignition On and Off to operate fuel pump. Pump two quarts of fuel into a fuel can. This will purge fuel pump. Install fuel fill cap.
17. Remove fuel line from container and attach fuel line to filter inlet.
18. Prime fuel system.
a. Cycle ignition on for 5 seconds and then off for 10 seconds.
b. Repeat step 18a twice.
c. Crank engine until it starts (maximum starter motor cranking time is 20 seconds).
d. If engine does not start, repeat steps 18a-18c.
19. Start engine and check fuel system for leaks.