So I have the motor out of my 94 Cherokee and its a 4.0 high output and I know the from 87-90 is when they had the standard 4.0 in the Cherokees. My question is will my motor wire strait up to a pre-91 Cherokee?? I also know those older years had knock sensors and junk that the 94 does not have and does. Of need.

 

nope, the flexplate/CPS is different, TPS works opposite, and the ECU is totally different.

 

I'm not sure what the flexplate is but in regards to the ECU, i still have the 94 cherokee body (its just totaled) so couldnt i just takethe ECU out of the 94 and put it in the older cherokee? If so do you think that would be hard? I'm also gonna use my 94 trany and the t-case cause i have an SYE on it.

 

Nope you would have to rewire the entire jeep to make the CPS intake ect work in the 87-90

 

But you can still use the 94 engine in your Renix Jeep. I've done a few of them. Keep your electronics and use the HO engine. Easy.

 

I've heard the term Renix jeep but I don't know what that is. Is it the motor on the pre-91's? Also how hard work it be to move the ECU from my 94 to an 89? Would that be all I'd need to do?

 

Renix is 86 to 90 fuel injection system. Using the 91 fuel injection stuff in your 89 would be a daunting task as far as wiring goes with no real benefit. Way more than moving an ECU.

What are you hoping to gain by using the 94 stuff?
Cruiser’s HO into Renix Swap
This swap is easier than some will lead you to believe, generally those who have never done it. Those of us who have done it, like myself, will share with you the things that need to be done for a successful swap. Just think of it as swapping in a long block.
The HO and Renix have some differences but none that can’t be overcome very easily.
Any HO engine from an XJ or ZJ through 1998 can be used. One running change was that the rear of the head was no longer drilled and tapped for the temperature gauge sender beginning in the 96 model year. The sender can be relocated to the threaded hole in the thermostat housing taken from the HO engine. You’ll have to extend the wire to that location. Some brave souls even drill and tap the HO head for the sender.
You will be using the intake and exhaust manifolds from your Renix, along with all your sensors and wiring. Since the intake ports of the HO are slightly different, you use the Renix gasket. Exhaust ports are identical.
You will need to use your Renix distributor as it is different than the HO because they use different fuel management systems. The flywheel or flexplate from the Renix must be used so your CPS gets the correct signals. The valve cover from the Renix allows you to keep your CCV system intact and requires no modifications.
The HO block will have a plug in the coolant galley on the driver’s side of the block, closest to the front, which needs to be removed so your Coolant Temp Sensor can be installed in it’s place just as it is on the Renix. It requires a 5/16" square drive or a modified 3/8" drive that has been ground down to fit. Do this before installing the engine.
As for the knock sensor, which is located just above the oil pan on the driver’s side of the engine about mid way, all the blocks I’ve seen are threaded for it. If not, I’ve heard they may be drilled but not tapped. Tap the hole if that’s the case.
　
Revised 07/24/2012
　

 

Just wondering im trying to retrofit a overhead console from a 94 limited to my 89 and the plugs for the harness.they arnt there and since im considering grabing the engine compartment and front harness..will the dash harness and ecu work with my 4.0....thanx for any help
STYX

 

There not behind the glove box i wired in the lighted visors from a 93 that plug was there?

 

The light plug is the only plug that will be there. The power to the console and temp sensor wires will need to be added.