i have a 1990 f-150 with 5.8 and e4OD, grandpa's truck has been sitting for about 5 years.. put a fresh battery in and it fired right up. drove it out of the barn and up to the house. ithen proceeded to tune up th e engine. cap, rotor, plugs, wires, and changed the oil and filter. Also drained the transmisiion and changed the filter. truck was running good at this point. I then drove the gas station 1/2 mile away put 10 gallons of 93 octane in the rear tank wich was almost empty, and added a full can of sea foam to the tank. brought the truck home and let it run in the yard for about an hour. got the truck ready to drive and topped off the radiator. at this point the the truck started to sputter and then died. My first thought was the sediment from the tank plugged the fuel filter, so i then replaced the in line fuel filter, and still not able to start the truck.. at this point i was able to start the truck with a shot of ether. battery was getting low so i put the battery on charge for the night. the next morning i tried to start the truck with either and it would not fire.. at this time i found that the ground wire from the battery to engine block was corroded in and broke in two, so i replaced it. i have run a check on the coil and it passed i did get one bad reading on the ICM mounted on the side of the distributor, so i replaced it. and still i have no fire..the test light on the tach side of the coil when i crank the engine over it just goes dim and it does not flash or pulse like it getting any spark. if the fuel pressure is not adequate will the PCM not allow spark. or is it possible that the faulty ground damamged the PCM. i need this truck running and i'm at my wits end.. HELP

 

Fuel ayatem. Pump maybe. Get a gauge and test the pressure. I also know some EFI engines had 2 filters and there were 2 tanks so they used a switch that frequently especially after sitting for years fails. Could be the other tank will work..

 

I'm not aware of lack of fuel pressure preventing spark - this is most likely an electrical issue. Check ALL your fuses with an ohmmeter.

 

Bad grounds to start with, so that would be my shot in the dark without playing with the truck.

Anyway, 1990 would be single high pressure pump in each tank with one fuel filter.

Do either of the pumps cycle when you key on?

Do you have a Haynes manual?

Do you have a mulitmeter?

Why fill it with 93 octane?

Why choose the general discussion instead of the basement pre '97 forum section?

Adrianspeeder

 

thank you for the input,, I have check the grounds and i do hear a click sound at the tank but do not hear a humm or motor noise. I have been through my haynes manual to the point my head hurts. i have used an ohm meter to check all the componets that i could. I used 93 octane and the sea foam to try clean out any sediment in the tank. as i am new to this site i have not figured out how to use or find all of the forums or where everyone is hanging out where i coulsd get the most help..

 

The pre 97 section is where guys who are currently owners hang out and You would likely get your best help in there.. I used to have a solid handle on that model but muchh has been forgotten..

 

Well that is a start. Look for a 12v output at the fuel pump relay when you jumper pin A of the self test connector to ground that manually triggers the FPR to see if power is being sent to the pump circuit.



Adrianspeeder

 

when you replaced that ground wire did you get the proper one and hook it up to the correctly, there are 3 points it should be hooked to: block/starter, frame, and ground wires sticking out of the radiator support by battery. this being the third spot on the rad support.

 

Baa, crimp connectors bad. ^

If ya ain't gonna solder, at least use heatshrink over the crimp connector without that yellow bit.

Adrianspeeder

 

its not ours, it was a quick google search. I agree, heat shrink.