Q: 1993 Ford F150 4.9 straight 6 fuel pump keeps running, won't start, replaced relay and fuel pressure regulator, still having the same problem

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Fuel pump comes on then cuts off. Truck starts then stalls. Fuel pump is running constantly. Won't let truck start sometimes if I wait a few minutes. Pump will stop and truck will run. It started this about a year ago then after a couple days, it stopped for about 4 or 5 months and then it started again and after a couple days it stopped and is getting progressively worse. I've replaced relay and the fuel pressure regulator, both did not help

Hi, thanks for writing in. You need to have the fuel pressure checked to see if the pressure is low. The fuel pump inlet screen may be getting clogged causing the pressure to drop off but the pump will continue to run. You may need to replace the pump if it is not producing enough pressure. If you have dual tanks then you may have a defective switching valve in center of vehicle on frame. If you would like help, consider having an expert automotive technician from YourMechanic come to your home or office to test the system for you, and make or suggest any repairs as needed.

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