My 1991 Ford F-250 (5.8) has been my money maker for the past 2 years. I use it daily for work and it’s been super reliable—I really don’t want to give up on it.
Recently I took it to a mechanic to replace the exhaust manifold gasket. After I got it back, I drove it all day and everything felt completely normal. No misfires, no hesitation, nothing.
Later that same night, while driving about 60 mph on the freeway, the truck suddenly died. No warning, just shut off.
After getting it home, I started diagnosing it. The truck cranks strong but will not start. No sputtering or anything—it just cranks.
On the driver side of the engine bay, I found a plastic connector (2-wire male/female clip) that had completely melted. It looks like it was resting against a hot metal tube (I’m guessing part of the exhaust/EGR), and the heat fried the connector and wiring.
Since then, I’ve done the following:
Repaired the burnt wiring (cut back and reconnected)
Replaced the TFI module
Replaced distributor cap and rotor
Cleaned up connections as best as possible
Still no start. From testing, it appears I have no spark.
There is also a small gray cylindrical component (looks like a capacitor/noise suppressor) tied into that same wiring area, so I’m wondering if this is part of the ignition circuit that got damaged.
My questions:
What exactly is that 2-wire connector supposed to go to?
Could that melted connection have taken out my ignition coil or PIP sensor?
Is there a known wiring diagram for that section of the harness?
At this point I’m thinking it’s either:
Still a wiring issue in that ignition circuit
Bad ignition coil
PIP sensor inside distributor
Any help would be appreciated. I really want to get this truck back on the road.