Here lately I have worked on two different trucks. One 02' with just over 100k and the other a 99' with almost 300k on it. One is well kept and the other is not so much but they are both having issues with the wiring harness becoming brittle and the wire covering falling off. On one it hasn't caused any problems yet but it's the ones going to the vc's. And the other was the cps wires. On my truck I'm not having these issues and many others aren't either. So I wonder what caused this? And how to prevent it? How to fix it? And most of all that when trouble shooting, that it's not overlooked! One I found when cleaning up an engine looking for a leak. The other have me the fits. Truck would randomly shut down or cut out under accel or cruise. Always set the cel with a cps code. One day I had enough and decided to swap it with mine. Now the reason I was so hesitant was cause it had already been replaced with the ford grey. Well when I went to start the truck it wouldn't fire off. It's an 02' so i couldn't tell it was the cps cause the rpm's don't move till cranked. Decided to see if I had remembered to plug in the connector and when I looked I could see a lil copper showing. I had left the key on and probly not the smart idea but when I grabbed the harness, the truck recycled the ignition on sequence. Abs check, vacum pump and fuel pump all kicked on. I thought that was real odd so I moved it again and it all went off, then back on again. So I turned the key off and pulled the harness upfrom the bottom to the top and when I pulled the loom back all three of the wires were bare. The truck had been having this problem for a while. Glad the gremlin was found and taken out! Just something else to watch out for!

 

David,

Is the issue in a small area or is it the complete wiring harness. I have an 02 is why I ask.

 

bulla, i replaced the 42 pin harness from the plug to the trany/transfer case. the insulation was cracking around the big trans plug. maybe its just age, although that seemed to be the only one. how about rodents? i've seen that before.

 

Deffinatly not rodents. You can grab the insulation and it crumbles. Sorry bob but I'm just trying to figure out what causes it. It's not specific to any model, but maybe exposures.? Has anyone else ever seen this before?

 

Thanks David

 

Yea David, worked on a coworkers truck and the insulation on the wires on the plug going into the VC connector were bare about one inch back on pass side (02)

 

Brush on liquid elctrical tape can repair bare and chafed wiring. Check hardware and auto parts stores.

Here's an example I just posted on another thread. LINK There are other brands.

 

That's what I used for the cps wires!