I can't thank you enough for helping me. It was almost comical to read so many threads that were questions answered with hijacked threads with ford truck guys asking more questions then not a single resolution. I was so frustrated and in pain it crippled me working on it and you stuck through it all with me answered so many questions appreciate it.

 

Awesome!

How does it sound?

You’re welcome - glad you finally got it going.

 

It sounded good and idled for 20 seconds before it shut off and it also would stall yrs ago. I wanted to check valve lash anyway and felt it was a bit too tight on new valve so loosened to redo it.

 

Did it just die or did it sputter then die, as if running out of fuel?

Back to the firewall junction block - I’d been waiting for a customer truck of the same era to show up so I could get a pic - one showed up yesterday.

This is on a 93 K2500 7.4 so there’s a few more connections than what you will have but the primary power circuits should be similar.

The connection marked by the arrow is the battery feed - I’m not sure of the original color but I had to run a new wire for it last year. I’ll try to post details of what each circuit should feed later.

 

I realized my pic probably wasn’t much good since it didn’t actually show the connections. So here’s what they should be powering, based on the wiring diagram.

I’m sure you already know some of this but for the sake of clarity I’ll tell you everything I found.

1 & 3 - The gray wire is supposed to connect with the 3 orange wires. Individually, the orange wires run to the switch side of FP relay, oil pressure switch, and the other branches off to provide 2 battery feeds to the ECM.

2 - There should be a 20 amp fuse at this splice for the fuel pump. The pink/black is fed from the relay and the tan/white goes to the pump.

4 - I’m not entirely sure on this one. The 2 possibilities are the blower motor relay or a camper/trailer plug.

Since you finally got it to start, I’d highly recommend replacing these wires at the firewall. They’re actually fusible link wire - they perform the same function as a fuse but don’t have a single element that blows - the wire itself goes open in the event of excessive current draw.

Assuming they’re original (and it looks like they are) it’s very probable there’s a partial open inside one of them. You can either replace them all with in-line fuses or get fusible link wire.

 

Thanks for posting all that info I will replace the wires. #4 goes directly to the battery on the positive battery post.

I figured it stalled from no oxygen sensor and ecm unplugged. I have a new iac if needed too.

 

#4 isn’t the large gauge wire. It’s supposed to be pointing at the splice directly behind it - there just wasn’t a better picture so I was hoping the arrow would make it clear.

It looks like that splice is between a gray wire off the junction block and a red wire that disappears into the harness.

 

Now I understand thanks for clarifying.

 

Found something this wire on block has varying voltage all the rest have 12.78. It's all over the place.

 

When I removed wire from block i now have

consistent voltage