Fuel Woes?
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Cargo Master
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From: North Dakota
Fuel Woes?
I replaced the IAC on my father's 2000 F250 V10 thinking it may be the reason why the truck would not start intermediately. On Sunday the truck would not start again. It would just crank and crank. I put a stethoscope on the filler neck and had someone turn the key to "on". I could not hear the pump prime at all. I tried it 4 or 5 times and nothing.
Tonight I decided to spray in some starting fluid. The first couple of sprays it died and the third it fired right up and kept an idle. So I shut it back off after driving around the block and did the stethoscope thing again and this time I could hear the pump prime. After hearing it prime 2 different times I cranked and it fired right up. Could this be a pump issue or relay? How could I tell? Thanks in advance.
Tonight I decided to spray in some starting fluid. The first couple of sprays it died and the third it fired right up and kept an idle. So I shut it back off after driving around the block and did the stethoscope thing again and this time I could hear the pump prime. After hearing it prime 2 different times I cranked and it fired right up. Could this be a pump issue or relay? How could I tell? Thanks in advance.
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From: mt.prospect
17yrs ago I owned a 1988 GM car. All Gm cars from the late 80's had fuel pump failures. One way to figure it out was to kick the bottom of the gas tank tank with the key on (Boots helped out) when the car wouldn't start.Usually fuel pump would cycle immediatly. 
things you do when your young!
things you do when your young!
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From: Long Island USA
Yes, whack the tank with a 2x4 and see if it'll start.
If it still doesn't start (or prime), tap the fuel pump relay.
If you do have to replace the pump, replace the relay too. I've found on many vehicles that the relay has already been overworked. Or, that the relay was already going bad and CAUSED the pump to go out. What happens is resistance at the fuel pump relay contacts means not enough current getting to the fuel pump which overheats the fuel pump. Pump goes out. Fuel pump is changed, and goes out again in a few months. I know someone that had three fuel pumps put into his '95 t-bird in 9 months and then got rid of the car. When I mentioned the relay was probably causing it, he almost kicked himself for paying for three pumps (and labor).
If it still doesn't start (or prime), tap the fuel pump relay.
If you do have to replace the pump, replace the relay too. I've found on many vehicles that the relay has already been overworked. Or, that the relay was already going bad and CAUSED the pump to go out. What happens is resistance at the fuel pump relay contacts means not enough current getting to the fuel pump which overheats the fuel pump. Pump goes out. Fuel pump is changed, and goes out again in a few months. I know someone that had three fuel pumps put into his '95 t-bird in 9 months and then got rid of the car. When I mentioned the relay was probably causing it, he almost kicked himself for paying for three pumps (and labor).
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From: Long Island USA
It should be in a small black box near the power distribution box near the master cylinder.
If the truck has ESOF (shift on the fly 4x4), there will be TWO small black boxes. The fuel pump relay is in the box that has two different size relays. I think the other one is the PCM relay, not sure on that. The ESOF shift relays will be in the other small black box, they are both the same size relay.
If the truck has ESOF (shift on the fly 4x4), there will be TWO small black boxes. The fuel pump relay is in the box that has two different size relays. I think the other one is the PCM relay, not sure on that. The ESOF shift relays will be in the other small black box, they are both the same size relay.
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Cargo Master
Joined: Nov 2003
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From: North Dakota
I think Friday I am going to replace the pump and relay. My father uses the truck as a daily driver and I don't think he can wait again until the pump stops working to hit the tank or relay for testing. Sometimes it will run for 2 weeks without doing it.
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From: Long Island USA
Sounds like the typical fuel pump going - it hits a bad spot when it shuts off, and won't start up again. Until something happens, like a temperature change, vibration (slamming the door because you're pissed), or just because "it feels like it".
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