Cooked wiring harness - "emergency bypass harness" ?

TurboDennis

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Buying a project truck 1000 miles away. Seller's description leads me to believe that the engine wiring harness is cooked/damaged. It's misfiring on 3 cylinders, but runs.
My plan is to fab up a quick "emergency bypass" wiring harness, that would bypass the critical wiring in the main harness to help me make it home.

I have spare injector connectors, and ECU pins. So i want to make a harness that will plug into the 6 injectors, and the corresponding connectors on the ECU end of the harness.

My question is - what other wires should i consider bypassing in this manner? I have no idea which wires are damaged and causing it to misfire. Perhaps dizzy and ignitor wires? Crank sensor? Any other suggestions? Thanks!
 
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I would venture to say that what you're proposing would work on a 40, but not on an 80. There are too many controls on the throttle body alone to do what you're planning to do. The complete EWD is in the Resources section. All the information to do what you are proposing is in there.

It's a fair bet that only the injector wires are damaged, although it's usually 5 & 6.
 

TurboDennis

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I would venture to say that what you're proposing would work on a 40, but not on an 80. There are too many controls on the throttle body alone to do what you're planning to do. The complete EWD is in the Resources section. All the information to do what you are proposing is in there.

It's a fair bet that only the injector wires are damaged, although it's usually 5 & 6.

Yes, i've looked through the EWD's. I dont think the wires that connect to the throttle body (idle control and TPS) would cause the truck to misfire in 3 cylinders, so i dont think i need to touch those.

It's been my experience as well that the injector wires are usually the ones to go first. I wonder why that is the case..

Going ahead with my plan to bypass select (critical) wires on the harness is my only feasible option at this point. This is something i can do relatively quickly with basic tools. Removing the wiring harness entirely to inspect/repair/replace is too much of a job for an Autozone parking lot.
 
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please follow up on how this all works out!
 
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I misunderstood your "emergency bypass harness". If all you're trying to do is feed power to the injectors, yes, you can do that. Based on the way the harness is wrapped, it's unlikely that any wires other than the injector wires will have been damaged by the EGR pipe, which is usually the root cause of harness failures.
 

TurboDennis

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please follow up on how this all works out!
Will do! But be on the look out for "Real time help! - Truck died in West Virginia mountains in freezing temperatures" thread on Monday. LOL

I misunderstood your "emergency bypass harness". If all you're trying to do is feed power to the injectors, yes, you can do that. Based on the way the harness is wrapped, it's unlikely that any wires other than the injector wires will have been damaged by the EGR pipe, which is usually the root cause of harness failures.
Yes, that was my plan - to disconnect the injector connectors, and pull out their pins from the ECU connector, and make a harness that will plug into the injectors and the ECU to bypass those wires completely. I was just wondering if there are any other wires in the main harness that often get damaged and would cause the truck to misfire.
 

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