xartman59

I hope everyone can ponder this possibility...I've been told that Jeep Grand Cherokee's wiring uses soy based wiring bioplastics! Starting in the early 2000’s, car manufacturers began using bioplastics...My neighbors Cadillac had wires chewed on two separate occasions from squirrels, etc...Total cost over $4000.00...I bought have-a-heart traps and caught 38 squirrels that season...anyhow I did tell her my belief of the vegeable based wiring! Now my 04 Grand Cherokee has been doing similar with the trans & O2 sensor...engine light...time passes, goes out! You ever check out your courogated tubing wire channels about the engine area? Try moving them or squeeze > IT CRUMBLES! Starting to get my direction? We just had heavy downpour and when I started up in the rain - ENGINE LIGHT on - tranny misteps - I'll reset PCM if need...I believe that the rain is causing arcing, irregular flow or wires could be contacting metal at times! Like a nerveous nightmare...then there are the common known problems...

lawsoncl

I'm assuming the original poster figured it out sometime in the last 6-1/2 years.

I haven't heard of issues with the Jeep Cherokee wiring (regular XJ or the Grand ZJ/WJ) falling apart or being unusually prone to critter damage. I've seen plenty of issues with the early versions of the biodegrable wiring used in some foreign cars breaking down and flaking off though. I think it was Toyota that was sued with a claim that the soy based insulation was attractive to rodents. At some point they started adding a bitterant to the soy-based insulation to discourage nibbling.

Anyway, if you're looking for help, try posting in the GRAND Cherokee forum https://www.cherokeeforum.com/f5/. Finding out the code that was set would be the best place to start. It could be the throttle position sensor, a bad transmission solenoid, or damaged wiring as you suspect. Knowing the code will help point you in the right direction and get a better response on the forum.