I have a wrecked 92 f150 with a 4.9 efi.I want to put it in an 86 f150.How do I connect the efi computer and harness to it? is there a diagram available?

 

You will have to pull the entire harness out of the donor truck and put it in the 86. Fuel tanks with pumps and all.

 

Since the 300 in an ‘86 should be fuel injected, that would be against everything I’ve heard about using the donor engine’s wiring in another vehicle. I’d think all you need to do is swap out the long block out of the ‘92 and put it in the ‘86.

 

My bad, I didnt think any Bullnose trucks had efi

 

The 300 didn't get EFI until 1987. 302s had EFI in 85, I want to say.

It would be a lot of work to retrofit everything into the 86.

How wrecked is the 92? The front clip of the 86 should almost bolt up to the 92 truck, with the exception of the lower fender bolt. Boxes should interchange, tailgates are different.

 

If I’m wrong about the ‘86 not being fuel injected can’t you still just use the long block unless your goal was fuel injection.

 

Also when you swap out the fuel tanks for the EFI ones, the fuel gauge will read backwards with the 92's tank. Ford changed how the sending units operate from 86 to 92 and I found out the hard way when I did the EFI swap on my 84 F250.

It is NOT a plug and play setup, I had to make up a custom ECU EFI harness to add to the 84 truck. Then swap fuel tanks only to find the nasty fuel gauge issue!! Had to do some creative engineering of putting the 84's sending unit into the newer year tanks. It ran for over 10 years till I got a Oppy DP intake and went back to carb/DSII!