94 YJ 4 banger in a 89 MJ

[foreman1063]

Any body here done a similar swap. I'll have the motor with all accessories, fuel injection, computer and harness. Any thoughts on how difficult it will be tying the newer harness and computer to the older MJ?

[mnkyboy]

I started the swap but then I found a 91 MJ in the wrecking yard to steal the harness out of.

 

There is some info in my build thread that might be helpful.

[ownedueasy]

I have done 93 yj (I believe it was 93) 2.5 into my 92 mj. Only thing that was changed were motor mounts, and intake. Other than that it was good to go

[mnkyboy]

92 would have the same 2.5l MPI as you would have been swapping in.

 

The earlier MJs use a Renix 2.5l TBI so a swap is much more involved then it would be on a 91/92 MJ.

[JeepcoMJ]

You need a complete xj dash and engine harness to do the swap...the yj harness is too short in some places, too long in others, and cannot be made to work with the mj cluster from a renix.

[mnkyboy]

Before I found a complete MJ harness I was going to use a 95 YJ harness,I had it all roughed in .

 

The plan was to run the YJ set up as a stand alone and piggy back the sending units needed to run the renix gauges, I even had a pass through speed sensor to give the 95 ECU its signal while still being able to run the cable speedometer.

I was basically doing it like you would put 4.0l injection in a CJ or early YJ.

[foreman1063]

Ok, thanks for the input. I was hoping for more of a plug and play scenario but guess I'll have to roll up my sleeves and get to work.