Mad Pup

Replacing the entire drivetrain is an undertaking that would only be contemplated by someone who cannot bear to part with that WJ platform, which is something I can certainly identify with. I wish you a rapid recovery from the upcoming procedure so that you can then pursue the WJ project some more, hopefully keeping us updated here

Biggerhammer

Thanks.

After looking at the left over parts that were in the back of the WJ, I’m starting to think that the PO put in two different cams and or the wrong cam gear. There was an HO cam and a NonHO head laying in there spare tire well.

Mad Pup

To the untrained eye, components unique to the High Output engine might be regarded as being interchangeable with those of a standard 4.7 liter V8, so your guess about such a mistake having been made by the previous owner might turn out to be the key that unlocks the puzzle to get that vehicle roadworthy again.

Biggerhammer

Well, after getting over gallbladder surgery last week and having a bad case of cabin fever, my youngest son gave me a hand with the WJ. I looked over the head and extra cam that the PO left in the spare tire well. They are in fact non HO parts. So, I decided to remove all of the new coils and swap them around to see if the problem follows them. We swapped them around and before I reconnected the harness I remembered reading somewhere that the pins would move around in the plugs. So I grabbed a pair of needle nosed pliers and pushed the wires into the plugs and then reconnected them. My son tossed the battery back in while I dug through my toolbox to find my terminal brush and clean the terminals up real good. We cleaned all the tools out of the engine bay so we didn’t end up with a 4.7 powered Cuisinart…

I jumped in and fired it up. It runs like a damn sewing machine now! Ugh, I was ready to burn this thing to the ground! Now to sell it and move on!

Mad Pup

Wow, I'd never have guessed that simply ensuring those wires were a snug fit would have such a dramatic effect and solve the problem with that WJ. Just goes to show how the smallest of details so easily overlooked can render a vehicle completely inoperable. This is a fantastic end to a real work of detective investigation, and I doff my hat in recognition of the dogged patience it took to solve this baffling puzzle. Your WJ has definitely been gifted with a new lease of life and is now battle-ready for some serious offroad adventures once again.