Hi, my name is Bud and I just bought a 1988 ford f-150 4.9L truck. I turn the key and the truck will start, but will not stay running. The truck has gas pressure, but acts as if it's getting no gas. Fuel injectors are running constantly. Could someone please give me some input on what may be causing this??????

 

Start here with the self test.. Ford Fuel Injection.

I think you mean the fuel pumps are running constantly, the injectors are fired by the computer only when the motor is turning. If the pumps run on after the motor quits the fuel pump relay may be shorted, it's on the drivers side inner fender. Your truck will have a rail mounted pump and in-tank pumps, if either of these are dead it won't run. Fuel pressure should be 45-50psi on the fuel rail, you'll need a gauge to measure it, a simple tire gauge works in a pinch.

 

Thanks for the info. I'm leaning towards the fuel pump that's on the frame rail under the drivers door.

 

My truck would not run at all when the high pressure frame-mounted pump failed. Can you hear any of the fuel pumps running? They all run off of the same relay, so if the in-tank pumps work while the frame pump does not, the fame pump is bad (unless of course there is not 12V at the frame pump connector when the other pumps are running).

 

thanks for everyone's input on this truck, however, I've had enough with the fuel injection and have decided to put a 302 in it. I'm starting the work today. At least with a carburator, I know how to fix it... thanks to all again....