I am having problems with the 5.0 getting hot and then shutting down, it feels like it is starving for gas, hesitates and then quits. it has no real consistancy but happens on and off trail. let me explain in a few examples: 1. fathersday, drove from park meadows to rollings pass, shut down to air down and starts back up fine, run for 1 hour or so and then it starts to lack for fuel. let it set for a few mins start up again and we only get 10 feet furthure down the trail. replace fuel pump with spare and runs fine the rest of the day and the following week. 2. went to bill moore today and drive from park meadow to the trail and get halfway into trail and it starts to bog again. this time i bleed off all fuel pressure from the rail and it runs again for 15 min before it bogs again. i stop, reduce pressure from the line and take out the puller pump (i explain later), put back together and it ran fine the rest of the day.
the setup: for the fathersday run i had a pusher pump only, when i returned from that trip i replaced the fuel regulater, fuel pump relay, added a puller pump (from the tank to the pusher), blew out all gas lines and cleaned the screen in the tank. Am i overlooking something electronical or ignition? help?
tia
shawn

 

Test the coil - they can do that when they get hot. The Haynes manual has a very thorough and detailed procedure.

 

It sounds like the pick-up coil in the distributor is getting hot and shutting you down. I have seen 3 trucks do this. After it sits for a short bit, it will restart and run then do the same thing. I just repaired one for that on Saturday.
Jimmy

 

what type of repair is this, and how. i know where the coil and dizzy is but the pick up coil is a ?. would love to know more or i could just look it up
tia
shawn

 

The pickup coil is in the distributor. This is what sends the rpm signal to the computer, as well as telling it when TDC is.

 

It's a magnet piece under the rotor button that reads as the 8 vanes on the shaft pass by it. It isn't the easiest thing in the world to remove, Depending on the mileage of the truck, you may just want to put a new dizzy in it. This is how I fixed my dads 89 and the other ones that I did, I installed a good dizzy out of another engine. Cured it every time.
Jimmy

 

I priced a lifetime reman at CarQuest for ~$90 for mine, but it turned out to be the coil - not the PIP.

 

Thanks for letting us know what fixed it. I have actually seen very few coils go bad. It does happen, but not real often. Especially the ECC IV ones. I have never had to replace one and I have worked on them for years. I have replaced a boatload of modules and quite a few pick-up coils though.
Jimmy

 

Same thing happened to my '86 F150 4X4, 5.0l EFI. Thought it was a fuel problem but it was a bad pick up coil in the dizzy. It started great cold but as soon as it was up to temp. it started behaving like it was running out of fuel. I think that condition is what shreaded my timing gear set.

 

This sounds like what is happening to my 96 E150 van. Last two day after the temp went over 100 in Denver, my van stalled like it ran outta gas, wait 2-3 hours and it runs fine. I've had two tow truck drivers tell me this is vapor lock due to the high temp and the altitude in Denver, but while possible I'm not convinced.

Anyone have any troubleshooting suggestions I could try before I swap out the distributor?

 

Check the fuel pressure when it gets hot and won't start, if it is above 30lbs, then it is not a vapor lock problem. This is very unlikely to happen on an injected engine anyway, because the fuel is always moving and when it is not needed at the injectors, it goes back to the tank. When the engine is carburated, the fuel will sit in the line until needed, and this is what causes it to boil into a vapor.
Jimmy

 

UPDATE: after replacing the fuel lines, efi,coil, fuel regulator, fuel pump and filter, dropping the tank and installing a line guage. we have found out that it is the heat in the tank causing the thing to stall. (at least that is the best clue we have right now) It still stalls. You can watch the pressure drop from a consistant 30 psi at rail and stumble to 10 or less psi. even if you direct wire the pump it will not push up to 30 psi until the whole jeeps rests and cools down, then she will jump to 30 psi and run until it warms up again. HERE IS THE BIG ISSUE, the fuel in the tank seems to be around boiling the boiling point. you take the fuel filler cap and you are unable to put your finger in the fill tube due to high heat. the exhuast is running around the tank but not overly close and i would not say that it is exhaust only. Why would the fuel in the tank be heating up so badly? please offer ideas.
thanks
shawn