will a 89 brain work on a 98 xj.
1989 Jeep Cherokee 4 x 4 that had a 4.0 Inline six, 5-speed transmission and power everything.

the 98 is 2wd 4.0 6 5 speed but not everything is power.


will it work out?

 

No. Call the dealer and ask what part# ECU's will work with your Jeep. Check ebay for reman'd or one from a C4C car.

 

Not even close - the 89 is RENIX, and the 98 is OBD-II.

As you get later and later in model years, interchange on control electronics is less and less. You're going to have to find a PCM for a 1998 w/242ci and AX-15 (power accessories and door count won't matter. Power accessories aren't controlled by the PCM.)

You should be able to score a decent unit from a C4C victim (make sure it's a 1998. The wiring gets shuffled a bit every year...) or get a reman from the aftermarket (I'd get one by A1Cardone or ACDelco.)