Can someone explain what happened here? I was low on fuel front tank, swictches to rear, slight hesitation (first time ever that happened, and I switch a lot) truck kept going 30 miles then died. Tow truck takes me to station, 5 gal front and rear tanks added, no fuel to rail (302 EFI) either switch. But at that time it would fire with either. Changed fuel filter (307k mi on truck, very well maintained),. now I have fuel to injector line, BUT NO FIRE! There is power to coil and that's it. Had starter tested, all good, replaced coil pac, replaced fender solenoid, replaced ignition switch, triple checked fuses, (one 20 amp large fuse bad, letter"I", don't know what its for), replaced PCM Diode. ( the 20 amp did blow again when I was trying to start and switched selector to "rear" tank.) Still no fire to distributor from coil. Test light won't come on small soleniod wire with key on or off. All battery , starter terminals cleaned, won't turn over in neutral.
Did something happen to fuel tank selector? Both pumps wouldn't have went bad at once could they?
The engine will turn over when I short fender terminals but won't start. The only other thing I didn't change was fuel pump supply fuse and fuel pump relay.
Gratitude isn't close to what I'd enjoy if someone could guide me through here.
Or else its pulling both tanks and seeing what i can find....
Thanks, Donald in KC

 

The PCM relay next to the Fuel pump relay must energize first, before the fuel pump relay is energized.check all fuses & fusible links. then follow power flow into & out of the relays (fuel & PCM relays appear the same but are not internally/ not interchangeable).

A potential curve ball is if pumps are still initially reaching system pressure, & the ECU it toasted, your injectors wouldn't fire, so the pressure stays the same & the pumps would not be called on to sustain pressure after the injectors opened (because their not opening). Fuses & fusible links blowing implies a dead short somewhere. Especially immediately after replacement. Hope this helps. Running a KOEO (key on engine off) error code scan may help. Even if all is well, you should receive 11 or 111 code. What year?

Parts ignition wise that could fail are the coil itself, the PIP sensor (stator) within the distributor, which should show on an error code scan, & your TFI module (which you can take in for bench checking). If you TFI is mounted on the distributor, it shares the same power & ground as the PIP, & both should be replaced at the same time.

Here's some helpful links. Ford Bronco2 EEC-IV & Ford Fuel Injection Stator (RPM) & Equus Innova 3145 OBD-I Ford Scan Tool

A favorite quote of mine it " How'd I get in this hand basket & where are you taking me? Is it getting hot in here..... or it it just me? I alway's thought IRS agent's would be much taller"

 

I grettly appreciate your help, even though I don't understand half of it. But I have a friend that is looking at truck tomorrow ans I will show this email. It's a 1994 xlt, 302 EFI.
I put fuel filter on and getting plenty of gas, what is the PCM? (PMC)?
thanks for your time to help me.
Donald

 

I had a similar issue when I first bought my 94 and the problem was the the fender mounted ground on the inside passenger fender. It's right behind the solenoid. Took off the wires and wire brushed evrything. Problem disappeared for good. That's after 3 days of randomn parts replacing/head scratching/cursing.

 

I dunno if this helps at all, but some fullsize passenger cars of that vintage have the PCM ground directly at the battery - I've had at least one car that was surging and was low on power that got cured by simply switching the PCM ground from the fender to the battery directly.

 

Power Control Module aka EC. or the computer.