How to Troubleshoot a Ford Econoline Fuel System

Check the fuel pump fuse. Pull down the fuse box cover, and remove the fuse for the fuel pump using the fuse puller inside the fuse panel. The metallic strip inside the fuse panel should not be broken. If it is, replace the fuse with one of the same amperage.

Put your key into the ignition, and turn the ignition to the "II" position. Listen for a faint humming sound. This humming is the sound of the fuel pump priming the system. The relay for the pump energizes, and that is what produces the momentary hum. If you cannot hear your fuel pump prime, then the pump has almost certainly failed. The pump is near the rear of the vehicle; you should definitely be able to hear it if you are listening carefully. The relay and pump assembly is what pressurizes the fuel system. So if you do not hear the pump prime, then the fuel system is not pressurized and will not deliver fuel to the engine. When this happens, the pump and relay will need to be replaced by a professional mechanic.

Turn the engine on and check for fuel leaks under the van anywhere from the gas tank to the hood. Since the fuel lines run underneath the Econoline van, instead of through the vehicle, the lines are prone to rust and corrosion if you live in a humid or corrosive environment (i.e., near the ocean, in northern climates where road salt is used to de-ice the roads, etc.). With the engine is on, the system will be pressurized, so you will see any fuel leaking from under the vehicle. Any fuel leaks in the lines must be fixed. This normally means replacing all the fuel lines.

Open the hood. With the engine still running, check the fuel filter mounted on the firewall. The fuel filter is a small canister where the fuel lines from the fuel tank converge. You can trace the lines from the back of the van all the way up to the filter. Check for any leaks. A fuel leak at the filter is normally caused by damaged or defective banjo bolts that connect the fuel lines to the fuel filter. In this case, new bolts must be purchased and installed from a Ford dealership. The filter itself can be faulty. If the fuel filter has more than 30,000 miles on it, you should replace it.

Check for hesitation at low RPM. While driving, if you experience hesitation when the throttle is wide open (the accelerator pedal is all the way to the floor), this indicates that the fuel injectors are dirty. In some cases it indicates that the fuel filter must be changed because it is clogged with contaminates. The fuel injectors will likely need to be removed and cleaned by a professional mechanic.