I have a 1992 E-150 4.9 with 110K. Last week truck would crank but not start and had it towed home.

It seems that it was not getting fuel as the fuel pump did not start up for the two seconds when I turned the ignition to the run position (I only heard a click after the two seconds) and there was no pressure in the schrader valve on fuel rail when I depressed it.

Earlier this week, I jumped my ten year old original battery and the fuel pump went on for the two seconds a few times, it started and died out. I tried it again but fuel pump never came on . Last night I put a new battery in, turned the ignition to the run position and the pump started, did it a few times to fill the lines and it started right up and ran fine until I turned it off after 15 minutes and tried to re-start. Back to the same old thing.

I had this crank and no start a couple years ago when the engine compartment was filled with snow after a blizzard and the coil wire was loose. Dried it out and replaced the wires and all was fine.

So far I have replaced the fuel filter and spark plugs.

Any ideas on what may be wrong (fuel pump, fuel pump relay, ignition system, etc.)? I am about at wits end.

Any help would be greatly appreciated.

Steve

 

OK, I squirted some throttle body cleaner into the throttle body and it started right up and died right after from fuel starvation, so I guess I can rule out the ignition system.

Please bear with me as I just purchased a mulitester and have never used one before. I checked the voltage at the green/yellow and pink/black wires at the inertia switch and it showed no voltage with the ignition in the off position and 6 volts with a steady drop with ignition in the run position on both wires.

I also have a running '87 E-150 that has the same 300/6 with the only difference being that it has the TFI ignition system instead of the Duraspark II on the '92. I checked the voltage on the '87 at the same two wires at the inertia switch and they were 0 at both the off and run positions (the fuel pump primed for the two seconds in the run position) and the wires showed 12 volts when the engine started.

I am just wondering why I have only 6 volts with a steady drop on the '92 in the run position and had 0 volts on the '87 and it starts right up? I swapped the horn relay for the fuel pump relay in the power distribution box but it did not make any difference.

If anyone has any ideas I sure would appreciate it.

Thanks,

Steve

 

Please don't pay attention to my first two posts (the'87 had 12 volts for a second when it primed the line).


On the '92 I am getting 12 volts for about a second at the inline connector at the top of the gas tank and then the voltage drops down slowly with the ignition in the run position. Since the fuel pump did not turn on I take it that the fuel pump is shot and it is time to empty the tank and drop it. Does that sound about right?

If anyone has any other ideas about what could be wrong before I drop the tank tomorrow, I am open to suggestions.

 

Steve, It is a good chance it is the pump. The wire connection on the top of the tank may show alot of cracking and is easily relplced. Check for a kinked hose also at the tank. MH