Fuel Pump Issue?
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Fuel Pump Issue?
I have a 1990 F250, 5.0 with duel fuel tanks. It has been sitting for a bout two months and when I went out to start it the other it day the engine would not fire up. Its just cranks like not getting fuel. I did some listening and have found that the fuel pump will not shut off when the key is in the "on" position. It used to and is supposed to shut off after a couple of seconds if the engine is not cranked.
I have checked and have spark. I can smell fuel, but not very strong. The fuel pump does the constant run no matter which which tank is selected. I replaced the fuel pump relay but that did not solve the problem. Would a bad fuel regulator or clogged filter cause this or am I looking at a PCM?
I have checked and have spark. I can smell fuel, but not very strong. The fuel pump does the constant run no matter which which tank is selected. I replaced the fuel pump relay but that did not solve the problem. Would a bad fuel regulator or clogged filter cause this or am I looking at a PCM?
Cargo Master
Joined: Jul 2009
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From: Des Moines
The fuel pump will run constantly when it has a constant source of ground. The PCM is responsible for controlling the ground signal to the pump via the fuel pump relay, so the PCM could be the cause.
However, it could also be a short to ground in the circuit, and if it were me, that's where I'd start looking first, meaning checking & cleaning all grounds for the fuel pump circuit. However, I don't have personal knowledge of where they are and I have no way to upload wiring diagrams. Subford can probably help you out with a diagram.
However, it could also be a short to ground in the circuit, and if it were me, that's where I'd start looking first, meaning checking & cleaning all grounds for the fuel pump circuit. However, I don't have personal knowledge of where they are and I have no way to upload wiring diagrams. Subford can probably help you out with a diagram.
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pnzrdvr
1987 - 1996 F150 & Larger F-Series Trucks
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Oct 24, 2004 06:18 PM
