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Ask A. Penland Your Own Question
A. Penland
A. Penland, Ford Senior Master Technician, ASE
Category: Ford
Satisfied Customers: 6162
Experience:  ASE Master Certified, ASE Advanced Gasoline Engine Performance
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1989 ford f150: rail..crank..only few seconds and die..pumps

Customer Question

i have a 1989 ford f150 that will not get fuel to it there is a electric pump on frame rail that you can hear turn on then back off again when you turn the key on. I pulled the outgoing line off of it and when you crank the motor it just dripps fuel is ann there is also a black resivior that all four lines coming from the dual tanks come into on the frame rail before the pump with two lines going out one a return i assume other to electric pump it will start and run for only few seconds and die then if you let it sit for awhile it will start and run for few seconds again. Is there pumps in tank and how could it be thay both went out or does that resivior or filter cartridge before electric pump have any thing to do with it or is that electric pump suppose to stay on? we changed the in line filter as well????
Submitted: 6 years ago.
Category: Ford
Expert:  A. Penland replied 6 years ago.


There are 3 fuel pumps on your F150. You have a low pressure fuel pump in each fuel tank and the one on the frame is the high pressure pump. Take the line off the back side of the pump on the frame and see what the fuel pressure is coming into the high pressure pump and the frame. You may just have a bad high pressure fuel pump.
When you turn the key on, the pumps will run for a couple of seconds and then turn off, that is normal. When the engine is running, they will run continuously. By taking the line off the back side of the high pressure pump, we can see if the in tank low pressure pumps are working. Let me know if you get fuel out of the line when turning the key from on to off a couple of times.

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Customer: replied 6 years ago.
when you crank it the pump on the frame rail runns while the engine is cranking yes but i have both lines off it and i pulled line off that black canister where the 4 lines come in from tanks and nothing comes out at all when cranking could both tank pumps go at same time or could the high preasure pump be bad cause it is running with lies off it
Expert:  A. Penland replied 6 years ago.

No, your problem is effecting both in tank pumps. One common problem is the fuel tank selector switch on the dash. Remove the switch and plug it back in to the harness. Turn the key on, you should have power on the RED wire when switched to the front tank and power on the BROWN/WHITE striped wire when switched to the rear tank. Remember you will only have power on these wires for a couple of seconds when turning the key on. Also check the connector to the switch, if it is melted or burnt, you will have to replace the switch and the connector and repair any burnt wires.

Below is the wiring diagram.