warrant_ero

I am having a strange problem with my 1989 F150 4X4 5.0 with dual tanks. I only have 74k original miles on the truck. The other morning i went to start the truck cranks but will not catch. Had to push truck onto the grass so my wife could get to work,

Truck had run fine the day before. I had to turn the key on to unlock the steering wheel so i could get it on the grass. After i had pushed the truck onto the grass I hopped in and it started right up.

I did switch between tanks when it would not start to no effect. Left the truck all day went to work came home the truck started right up.

I was think that maybe my high pressure pump was going bad or maybe my tank selector switch was acting up. Thoughts anyone?

88xlt

I would think it's more likely an ignition problem. I would do some testing if it does this again.

Spray some starting fluid in the air intake and see if you can get a slight response out of it. Pull the coil wire out a bit and watch for spark as the engine is cranked over.

warrant_ero

Check the fuel pressure 40 PSI engine off about 32 PSI when engine running. Truck has been running fine ever since. Anything on the ignition in particular I should check?

I could pull codes to see if anything popped a code.

88xlt

It's tough to check ignition components when the engine is in a running condition. I would suspect the coil or the PIP inside the distributor. There is also the ignition module on the side of the distributor, but in my experience when that goes dead it stays dead.

If it does this again and you determine it's an ignition problem, you may have to go trial and error on replacing parts unless you can test the parts before the engine will start.

Cweldy

Check the fuel pressure after it has been sitting. May have a bad check valve and is losing pressure when the pump isn't running.

sillydawg

My 93 F-150 did the same thing for about a month. Best way to discribe what happened to my back tank is that I had what I'll call a flat spot on the sending unit motor. it would run fine, parked it at night, No start in morning. I bounced the truck or sometimes kicked the tank. Got about a month out of it. Finally had to replace in tank fuel pump.