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So I have an 88 F-150 that was a 5.8 before I bought it. I got it for 350 bucks mainly for it's parts (axle and tires) since it didn't have a motor, but have decided I want to make it a driving truck again (since the title is clean and the body is in great shape).
The engine bay wiring harness was completely destroyed by the previous owner who ripped out the motor, so I don't have a good indication of any differences there may be with this wiring and a different truck's wiring.
I am one bolt away from pulling the entire engine bay and motor wiring harness from a 1989 Bronco that is a 5.0 from our local junk yard. Will that wiring harness be compatible with a 5.8 motor as long as I have the proper ECU? Also, can I pull a 5.8 motor from a 92-96 F-150 and use the wiring harness from the 89 Bronco?
The wiring seems very similar between my 94 F-150 5.8 and the junk yard 89 5.0 Bronco. My plan tomorrow was to grab the 89 Broncos entire engine harness, and a 90's 5.8 motor (because they have a bit of these and not ones from 80s.). I believe the only wiring difference between those would be the distributor, so I would need to get the proper year distributor for my 88 F-150, but otherwise I think that should be good.
So to shorten my questions:
1. Will an 89 5.0 Bronco engine wiring harness work on a 5.8 motor?
2. Will a 92-96 5.8 motor work on the 89 wiring harness?
3. Are there any differences I'll have to look out for?
1. Will an 89 5.0 Bronco engine wiring harness work on a 5.8 motor?
Yes
Originally Posted by Bubba Jones
2. Will a 92-96 5.8 motor work on the 89 wiring harness?
Yes
Originally Posted by Bubba Jones
3. Are there any differences I'll have to look out for?
The later trucks used a remote ignition module so the distributor wiring is different, the solution to that is to just use an early 5.8 distributor or retrofit the one you get. I did this with my 5.8 swap, the flat where the module would go is still there but the hole to connect to the internal PIP module isn't and the mounting bolt holes aren't drilled. That's easy to deal with though just cut an oval notch for the module connections with a dremmel and then drill and tap the two mounting bolt holes. Also note that if you get a '94+ motor it will have a roller cam so the distributor needs a steel gear.
The later trucks used a remote ignition module so the distributor wiring is different, the solution to that is to just use an early 5.8 distributor or retrofit the one you get. I did this with my 5.8 swap, the flat where the module would go is still there but the hole to connect to the internal PIP module isn't and the mounting bolt holes aren't drilled. That's easy to deal with though just cut an oval notch for the module connections with a dremmel and then drill and tap the two mounting bolt holes. Also note that if you get a '94+ motor it will have a roller cam so the distributor needs a steel gear.
Awesome thank you very much!
Sorry to clarify on what you're saying about the distributor but are you saying you used a (92-96) distributor with an 80's harness? Or are you saying you modified the 80's distributor to work with the 90's harness?
If I can use the newer model distributor on the 89 harness, and all I have to do is tap, drill and mount the ignition module to the distributor,e then modify the wiring harness to connect, that sounds super simple and I'd like to do that! If possible, I'd like to get a roller cam motor so I'd need the steel gear distributor and think using the one I get with the motor would be the best thing to do.
I used a late model('92+) 5.8 distributor on an early flat tappet motor in my '90 F150 with the original 5.0 engine harness, and the whole reason for doing this is so that the wiring harness does not need to be modified.
I used a late model('92+) 5.8 distributor on an early flat tappet motor in my '90 F150 with the original 5.0 engine harness, and the whole reason for doing this is so that the wiring harness does not need to be modified.
That sounds great! Thanks again for the info! Maybe I'll have my 88 F150 running this weekend, but I'm not in a huge rush.
I have a 94 F150 as well (apart from my Bronco and 91 Camaro) but it's my beater truck because it's super rusty. I was going to use this 88 to replace parts on the 94, but the 88 is in such good shape I think brining it back to life would be a better idea, especially since it has a good clean title.
I'm going to try and get a roller cam motor as well, but I'll see what motor looks the best first. Its been snowing a lot here in Cheyenne and some of these motors have the intakes off etc, so I'll need a motor that hasn't been opened up. It's surprising how many more motors (351s 460s LS motors) this junk yard has though compared to what was available back in AZ. AZ didn't really have a problem with rust and water getting into the motors...
I used a late model('92+) 5.8 distributor on an early flat tappet motor in my '90 F150 with the original 5.0 engine harness, and the whole reason for doing this is so that the wiring harness does not need to be modified.
Sorry to be a bother again but I had one more question. The distributor that came off the 95 motor has a round wiring harness plug coming off of it. There doesn't seem to be any place for this wiring to plug into the 89 wiring harness, there is just the connector for the TFI module on my harness.
Is this wiring off the distributor (for 92+) discarded for the older trucks, so I just plug in the TFI module after mounting it to the newer distributor and leave that round plug coming off the distributor dangling?
to sum it up, that plug is for the remote located TFI Module on the fender, on the 95 truck the motor came out of, Ford moved it, to help stop/slow heat soak on module
Yes this is what the distributor conversion is all about, the internal pickup module that wiring is connected to has to be removed and replaced with the earlier version that connects to the on-board TFI module, the internal module is just bolted in but you have to remove the distributor shaft to change it.
Yes this is what the distributor conversion is all about, the internal pickup module that wiring is connected to has to be removed and replaced with the earlier version that connects to the on-board TFI module, the internal module is just bolted in but you have to remove the distributor shaft to change it.
Thanks again for the help! I just pulled a distributor from a 89 f150 in the yard. I think I'm just going to swap the gear from the 95 distributor over to the 89 distributor since that seams like it may be the easier route! The 95 distributor was left without a cap for who knows how long and had mud and stuff inside, and the inside of the 89 distributor looked fine since it did have a cap.
I just got the cast iron gear off so now I'm going to take the steel one and hopefully push it back on carefully with the socket and hammer method.
That wasn't too bad to swap the gears! Just used a nice impact deep socket and had the distributor on top of a cardboard box with my spare cylinder head in it so the blow was somewhat softened.
That is the simple solution, I didn't realize you had an older distributor on hand.
Oh no I didn't until this morning at the junk yard. I didn't have the TFI module so I was going to try and grab one but figured I'd just take the while distributor while I was at it.
Unfortunately it appears that the older distributor won't work in this motor because the Allen section of the shaft that attaches to the oil pump is smaller... So I'll have to swap things over again or see if I can swap shafts.
Now looking at the shafts I'm not sure if they are interchangeable.
The one on the right is from the old distributor, and the left is from the new.
Is that groove near the top on the old shaft required for the pickup sensor to work properly? Because if so I can't exchange the shafts then... But the old shaft won't fit in the oil pump...
