J.W. Snow Jr.

Having trouble with the wiring harness for my 302. When I purchased this engine the harness was cut but all plugs are connected and so I am trying to use my plug from my 1995 f150 300 i6 and solder it with the old harness not sure but there are a lot of the same colors and they go to the same places I'm just not sure bc I have two or three wires without mates and have doubled or tripled some colors is this correct or have I fallen off my rocker again? I need some advice and I need my truck running please?

Chris_1

iTrader: (1)

Sounds like a really good way to frustrate yourself. Can't find the right harness anywhere ?
Time might be better spent hunting up a new harness - the way you're doing it might work but it really sounds like it's going to cause ongoing problems.

J.W. Snow Jr.

Could I use my old harness instead of soldering it?

Chris_1

iTrader: (1)

Ok, lets start at the beginning. What year truck and engine size came out ? What year 302 is going in ? (Does the I6 even have anything to do with it ?)
Give me a quick history lesson on your situation there, then I can help you figure it out.

J.W. Snow Jr.

Ok truck is a 1995 f150 4x4 the i6 was in it but I blew the motor I found this motor the 302 for cheap under 400$. Now I was going to cut the harness and solder the one that came on the 302 but I have a few colors that don't match and extra wires. But I noticed the harness that was on the i6 is the same as what's on the 302 so can I use that harness?

J.W. Snow Jr.

And idk the year of the 302 I think it's a 93-94 and came out of a mustang

Chris_1

iTrader: (1)

The harness on the I6 won't even be close to a 302 harness.
You need a 302 engine harness (if nothing else, there's 2 extra injectors that need wires, not to mention that all the sensors are in a totally different spot).
You also would probably need an engine compartment harness that will carry v-8 signals from the computer.
I think that what you need to do is find yourself a 95 (maybe at the wreckers?) with a 302 and strip the wiring from the firewall forward and swap it over. You'll also need the computer to run a V8, your I6 computer isn't going to do it.
And then you need to know for sure if that mustang motor has the HO cam in it which is a different firing order, but it is the firing order used in 95 302's.
Honestly that's just the main stuff, there's a lot of other little details.
I admire your willingness to work, but maybe you should put the brakes on things for a little bit and do some serious research into what all is required to do a v8 swap. It's not really just a quick swap and join up a couple wires. But it has been done lots of times, by guys right on this site, and they probably wrote up a step by step - if you're really lucky, there'll be pictures.
Take a little time to get your ducks in a row, then we'll try and help out with the details.

J.W. Snow Jr.

I got one from a local salvage yard and I also have the computer to change it to a v8 it's just switching it over is my problem some of the plugs don't go on my truck

Chris_1

iTrader: (1)

I know they all sort of look the same under there but the engine compartment and engine wiring harnesses changed from year to year, engine to engine. Also the computers are set up for the motor and transmission combination. So.. to put a 302 into a 95 you would really want the wiring from a 95 with the same transmission to make it all work without getting into repinning wires.
A 92 (for example) with a 302 will have a mass density wiring harness, a 95 302 will have a MAF harness.
It's also important to know if the mustang motor you're swapping in is an HO or not. You can tell from the firing order - HO is the same as a 351.
95's will be wired for HO and MAF.