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XJ engine/transmission swap questions

CTeunuch

NAXJA Forum User
Location
MA
I have a few questions before I tear the heart out of my XJ and find out things won't work. The XJ is an 89, Renix/AW4/231, and the donor drivetrain is from a 93 ZJ 4.0HO/AW4/242. My only concern is wiring differences between the two as I don't have the ZJ's harness anymore. I know I'll need the Hesco TPS sensor adapter to run the HO intake/throttle body of the Renix computer, but is there anything else that won't be essentially plug&play? I have no problem cutting plugs from a JY and splicing them in to the XJ harness if need be, but will that be all? What about issues with the AW4 plugs between the 89 and 93? Thanks for any help and advice.
 
Swap over your intake and exhaust manifolds using the Renix gasket, sensors, distributor and flexplate/flywheel. Good to go.

I really want to ditch as much Renix stuff as possible. Not only for the power gain, but to get rid of as many vacuum lines as I can. The PO tore every line out, and then put them back in all wrong. I've searched everywhere but can't find the leaks, so I ended up adjusting the idle speed down at the throttle blade for now. My main concern is the transmission sensors and controls, because I'd rather not end up shifting it with a series of switches like I've seen some do. I can make the engine sensors all work based on info I've found online, but I haven't read much on differences in transmission years. Thanks again for any help.
 
I really want to ditch as much Renix stuff as possible. Not only for the power gain, but to get rid of as many vacuum lines as I can. The PO tore every line out, and then put them back in all wrong. I've searched everywhere but can't find the leaks, so I ended up adjusting the idle speed down at the throttle blade for now. My main concern is the transmission sensors and controls, because I'd rather not end up shifting it with a series of switches like I've seen some do. I can make the engine sensors all work based on info I've found online, but I haven't read much on differences in transmission years. Thanks again for any help.

There will be no power gain by eliminating the Renix vacuum harnesses.

Adjusting the screw on the throttle body is absolutely not the correct way to set the idle.

Vacuum leaks are easily found using throttle body cleaner.

When you need the correct procedure to set the throttle body back where it's supposed to be, post up and I'll give you the instructions.
 
There will be no power gain by eliminating the Renix vacuum harnesses.

Adjusting the screw on the throttle body is absolutely not the correct way to set the idle.

Vacuum leaks are easily found using throttle body cleaner.

When you need the correct procedure to set the throttle body back where it's supposed to be, post up and I'll give you the instructions.

First of all, the Jeep is junked and I don't know why this thread was brought back up.

Second, I wasn't trying to gain power by eliminating the Renix vacuum lines, I was trying to clean up the engine bay, and get rid of all the leaks/incorrectly routed lines. I know how to set idle properly, but that wasn't the goal. The goal was to get it to stop idling at 1500 RPM so I could drive and wheel it for a while. I tried to find the vacuum leaks using ether and throttle body cleaner to raise/lower the idle, with no luck. After gutting the vacuum harness and broken emissions crap I adjusted the TB back to the proper spec, and it idled fine. Never got around to swapping in the HO set-up as the Jeep wasn't worth it.

Next time you feel like being condescending with your 'helpful' advice, make sure the thread isn't completely dead:cheers:
 
It was brought back up because someone else responded to it.

You stated this:I really want to ditch as much Renix stuff as possible. Not only for the power gain, but to get rid of as many vacuum lines as I can.

And, I wasn't being condescending but suggesting better ways to deal with the high idle if all the other possibilities had been addressed, including spraying for vacuum leaks.. Very sorry you got your panties in a knot. I will try to do a complete forensic timeline of a complete thread from now on to eliminate this happening again.
 
It was brought back up because someone else responded to it.

You stated this:I really want to ditch as much Renix stuff as possible. Not only for the power gain, but to get rid of as many vacuum lines as I can.

And, I wasn't being condescending but suggesting better ways to deal with the high idle if all the other possibilities had been addressed, including spraying for vacuum leaks.. Very sorry you got your panties in a knot. I will try to do a complete forensic timeline of a complete thread from now on to eliminate this happening again.

I wanted to ditch the intake/exhaust manifolds to gain power, not the vacuum lines.

No need for a ' complete forensic timeline', the date is right up there in the corner of each post, so you could have just looked back two posts and seen it had been over a year and a half. Luckily I haven't been waiting here for that long just to get some basic advice from you on how to diagnose a high idle. Which, by the way, wasn't even the question I had asked, so the little input you offered was pretty much useless. Thanks for trying though, I'll give you a gold star for effort!
 
Believe me, you will never get another tidbit of advice from me from here on out. Too bad you didn't state things as they were and then clarified this much later regarding the manifolds. Communication and people skills are on the decline these days. You seem to know everything on your own. Unsubscribed.
 
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You shoulda done the forensic timeline before responding..........


Better late than never!!!! LOL, but I hear that broken vacuum lines suck!!!:laugh3:
 
I've seen this jeep, what a toilet.

Also: some 93 ZJs did get AW4s (only early ones) and Pat has been around the block before with jeeps, this isn't his first day working on them. If he said it was an AW4 it probably was.

I'm betting whompinxj found it while looking for info on the swap he's planning and didn't realize the thread was a year old before posting. No harm, no foul.
 
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