Problems after 4.0 swap

[jeepjeff859]

Here is a little background

I have 86 comanche that i did a 4.0 swap using a 1994 ZJ engine and a 95 XJ harness

I have a early AX15 with the internal slave

The problem

every time i go from a idle to moving the engine stumbles and falls on it face, i can power through it my lightly pressing on the clutch. Once moving it only does it when i give a little to much throttle or when i get to high RPMS.

I already replaced the TPS and IAC and CPS. i have around 30 PSI fuel pressure with the engine not running and 40 with engine runnig


I can rev the engine all day while the jeep moving and it wont do it and no codes pop up except my AC relay is missing since i dont have AC hooked up

 

[gradon]

Was the comanche originally automatic or manual?

 

[jeepjeff859]

It was a 4 speed

But when I did the swap I swapped every harness out of the donor XJ

 

[043500]

You may need to go through the harness wire by wire.

I put into an '86 (go figure) MJ a 94 YJ 4 cyl with a different year harness also from a 4 cyl YJ and had at least 2 wires that did not match up color and/or position wise.

You're using a different year AND different vehicle engine vs harness. Stands to reason something doesn't quite match.