My dad has a couple of different Ford trucks, one is a late 80s 4WD ranger with a V6 and the other is a late 80's full size with a 300-6. First it was the Ranger, it was starting ok, then one day it wouldn't stay running. You can hear the fuel pump running for a few seconds when you turn the ignition on. It'll hit every time you try, but only run for a second or two. Now the full size truck is doing the same thing. A friend said it might be the fuel pump solenoid and suggested trying to hold the key over into the start position to see if it stayed running, but it still does the same thing. I haven't taken my tools out to his house yet to check the fuel pressure, but plan to when the weather gets a little better.

Any ideas?

Thanks

Jon

 

From what I've heard, I suspect you have a fuel delivery problem all right, but I don't know about the solenoid - you shouldn't get any fuel at all as I understand it.

Does it have dual tanks? I think each tank has its own pump, try swapping tanks....but eventually you need to measure fuel pressure at the rail. (Assuming it's fuel injected?)

Since it runs after you release the key, I doubt it's electrical, but here's a story for you....

'77 Corolla. They use something like a 7-volt coil - so voltage is knocked back by a ceramic/wirewound ballast resistor that sits next to it. But when you're starting it, resistor is bypassed so the coil gets the full 12v as a boost.

WHen these resistors fail - the inside is delicate, the resistance wire's wound round a glass rod - the engine will start but die as soon as you release the key, since as soon as key's released power to coil's routed through resistor again.

Fuel starvation could also be due to an extremely clogged fuel filter, but be warned there's a technique (and special tool) for changing them. Water in the fuel can also behave that way, although you may get some spluttering too. I suppose for that matter, I assume there's plenty of gas in the tank? If it's really low, there could be a problem with continuous supply there too.

 

I would agree with 999. If one truck started having the problem and now the other one is doing the same thing I would have to suspect a fuel issue. Do you buy your fuel from the same station? Do you have your own bulk fuel tank that you fill these trucks from? Sounds like water may be in the gas tanks or the gas has contamination and has plugged the fuel filters up on both of these trucks. Any possibility that someone is introducing water,sugar, or some other contaminate in the gas tanks of these trucks? Good luck

 

I would suspect the ignition TFI module or possibly the ignition switch.
Reason: These systems have ...two... inputs to the TFI.
One for starting and one for running.
The ignition switch, switches between the two inputs.
A failure in the run position will allow the engine to crank fire but not run when starting is released.

 

Thanks for the replies so far. I did Forget to mention that both are fuel injected. Neither of these trucks are tagged, so they haven't left the farm for awhile. My dad just starts them weekly to keep the batteries up, etc. I assume he's just bringing fuel home in jugs, but I'm not sure if any fuel was added between them running ok and not. I'll have to check. I would guess that he gets all his gas at the same place and he's not had any problems with his daily drivers. I think it may be awhile before I can go check them out as we have a few inches of ice covering everything here in Missouri. I'm wondering now if the fuel guages work and whether or not he's been siphoned! I'll be back with more infor when available.

Thanks
Jon