Engine wiring harness??

[HotRodPC]

www.truckandcarshop.com has a large selection of harnesses, both repro and NOS. However, They only have them for 73-82. As soon as I can find out if the 82 engine harness is compatible with the 86 I may be picking one up.

the only engine related stuff on an 82 is the choke, oil presure, temp gauge, ignition...unless you have the electronic timing with the knock sensor. what exactly are you trying to do?

He MIGHT be able to get this to work. The Engine Harness itself, should be the starter, Alternator, Dizzy Power, Gauges and Choke right??? I'd like to know for sure myself. I do know on the 81's, the AC harness is stand alone and not part of the engine harness, and on 81 and 86 both, the ESC harness is also stand alone. The engine harness comes out under the Brake Booster, the ESC harness comes out of he firewall in the hump just to the passenger side of the Dizzy Cap. The AC harness comes thru the firewall on the passenger side of the firewall also.

What I don't know, is if the Pin Outs are the same on the different years at the firewall off the fuse block.

 

[Jims86]

Yeah, mostly just starting, charging, and gauges if hedoesnt have the knock system. not worth buying a whole new harness. new wires and connectors solder spliced into the firewall plug in under 1/2 a saturday.
I just incorporated TBI harness to Cali''s 84 firewall plug. not a lot of wires there.
The 85-86 fuse cavities are different from earlier and later models.

 

[HotRodPC]

Yeah, mostly just starting, charging, and gauges if hedoesnt have the knock system. not worth buying a whole new harness. new wires and connectors solder spliced into the firewall plug in under 1/2 a saturday.
I just incorporated TBI harness to Cali''s 84 firewall plug. not a lot of wires there.
The 85-86 fuse cavities are different from earlier and later models.

The knock system is stand alone with the ESC wiring from the ECM. There's not much to it. You have an ECM behind the glove box. Wires that go to the dizzy for managing the timing, and the wire going to the knock sensor. That's about all there is to the ESC, along with a wire to the Check Engine light. That is all stand alone and not part of the harness from the fuse block.

At least that's how it is on the 81. The ESC is stand alone form the Engine Harmess.

 

[hootsmcgoots]

the only engine related stuff on an 82 is the choke, oil presure, temp gauge, ignition...unless you have the electronic timing with the knock sensor. what exactly are you trying to do?

I have an 86 which originally had a 4.3, converted to a 305 3 PO's ago. The harness issue extremely worn, oil soaked wires, damaged connectors, etc.

 

[HotRodPC]

I have an 86 which originally had a 4.3, converted to a 305 3 PO's ago. The harness issue extremely worn, oil soaked wires, damaged connectors, etc.

That's good, AT least you have something to match it up with. I wouldn't imagine the 4.3 Harness is much different than the 305 or 350 harness. Maybe a hair shorter reach on some of the wires going to the front of the motor should be about it.

 

[89Suburban]

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[HotRodPC]

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That's obviously TBI 87 or newer. But even then I think the TBI and all related senors, the harness is separate from the fuse block harness isn't it?

 

[hootsmcgoots]

That's good, AT least you have something to match it up with. I wouldn't imagine the 4.3 Harness is much different than the 305 or 350 harness. Maybe a hair shorter reach on some of the wires going to the front of the motor should be about it.

That's what i figured. I was mainly worried about the plug styles/pins matching.

 

[Jims86]

That's obviously TBI 87 or newer. But even then I think the TBI and all related senors, the harness is separate from the fuse block harness isn't it?

except for 2 wires iirc, yes. and there should be no differences between the v8 and 6 harness. I have not seen any replacement engine harnesses in the aftermarket newer than 82, and that may plug into the 86 cavity, but the in common plug positions may not be the same.

 

[HotRodPC]

but the in common plug positions may not be the same.

And that's my concern. The Pinout being different. And what makes me think there is difference, is when did the fuse types change? Went from the glass tube fuses to the colored flat spade fuses? That is what makes me think the Pinout could very well and likely is different. Then in 84 the Multifunction turn signal switch came about, so again, that made a difference in harnesses, but that may only affect the under dash harness and not the engine fuse block harness.

Seems I was told at 1 time, the 84-86 underhood harnesses were identical. For the life of me, I can not recall where I seen or heard that info. I've been looking for it and can't find it.

 

[89Suburban]

Yah that's out of the 90 manual just felt like throwing it up.