Between my two brothers and I we have owned a 94 3.0 5 speed since late ‘98. It is an eyesore but has over 300k miles on original engine and trans and has had the dog crap run out of it. The truck sat for an extended period last year, I took it back from my brother, and put it back on the road.

There was a hesitation issue with it, I replaced plugs, wires, cap, button, and coil. Still had some hesitation, I replaced fuel filter, pump, fuel pressure regulator, and cleaned out the gas tank. Truck ran better than it had for ten years.

A month ago the truck died on the way home from work. Just shut off. After five minutes of cussing thinking it was the new fuel pump, the truck started back up and ran fine. A week later it shut off in the driveway and would not fire. Crank but not start. I swapped an old coil I had and it started, ran for two minutes, then quit and proceeded to melt the tack lead on the aftermarket tack I put in back in 2011.

Investigation led to the discovery of where the tack lead came through the firewall and that the wire had been chewed, exposed, and grounded out courtesy of a - - - - ing mouse.

I removed the tack and all associated wiring. Truck will not attempt to fire. Someone said the distributor got burned up, so I replaced it. Still no go. Someone else told me the ignition module on the fender got shorted out, so I replaced that. Nope, that didn’t fix it. Another person swore the ignition switch got toasted. Guess what?

I did some more detective work before I spent anymore money. The coil has a dead lead going to it. I have power at the red/black? lead, but no power at the yellow lead with the tan stripe. I traced the wire back over to where the main plug comes from the cab through the firewall. There is no power on that lead with the ignition switch on. I have scanned the truck and get no trouble codes. All the fuses inside and out check ok. I have checked all the relays and the scanner says they are ok, swapping them around verifies a no start condition.

Sorry, my wife says I ramble. My question to everyone is this: Did I toast something somewhere in the wiring harness? Or is it possible the main computer got ruined? I can’t tell by checking all the wiring diagrams if that dead lead even goes to the main pcm.

The truck has a lot of sentimental value, or I would have done called the scrap yard. I’ve already broken down and pulled the dash (that sucked), prepping for the worst.

Any and all help is appreciated, thanks for being patient reading all this

 

Welcome to the forum

First do 50/50 test
Spray gas/fuel into the engine and try to start
If it starts, spark is OK, fuel delivery is not OK
If it doesn't start then spark is not OK or compression is not OK
50/50 no guessing, spark or fuel issue

FYI, its the only way to test if spark and spark timing is OK, especially on later models without distributors

In 1994, and earlier, Rangers spark is run by a separate module(TFI on yours), Computer only runs the fuel injectors so can't effect spark working or not

Coil "+" gets 12volts with key on, that 12v travels thru the coil, to coil "-" and out to TFI module AND Tach wire, this is why grounded out tach wire did the smoke show, and shouldn't have hurt anything else, but.................
Coil "+" wire could have been effected
If there is no 12v with key on at the coil, either terminal then thats the problem
In 1994 there was no fuse it just gets 12v from ignition switch under steering column on a red/green wire
Same red/green wire powers distributor sensors and TFI Module on fender
They all need that 12v with key on, from ignition switch

 

Sorry, should have mentioned fuel pump is working and I have fuel at the rail. Thank you for the feedback-looks like I will be replacing some harnesses.