I plan to put a 4.0 xj engine from a 93 xj into a 98 xj what do I need to use from 98 to make the swap. I have been told to use the 93 as a long block and use the bolt on parts from the 98. I need to know which bolt on parts to use and what is meant by "bolt on parts" thanks for any information I can get.

 

Bolt on parts = anything that bolts to the engine (alternator, A/C, intake manifold, exhaust manifold, anything with a sensor attached to it.....). Make sure that "new" engine is in good working order before putting it into your 98.

 

'93 head has a temp sending unit at the rear drivers side. '98 XJ does not have a wire that plugs to that sensor.

 

The engine is out of my 93. Engine had 80,000 miles on it when I totaled the 93 when I finish the build on 97 it will not be driven on the road will be trailered to and from. So don't need emissions just gages. Do I really need to change in take and exhaust manifold.

 

You will need the right head for your year for that sensor, if not the EMC will not work properly for the engine to run period.

 

Yes. All of 'em. Distributor, flywheel, manifolds, brackets, ANYTHING electrical. As mention the OBD-II 4.0Ls no longer use the temp sending unit at the back of the head, so just leave that sensor screwed in like a plug. Beats a coolant leak! New PCMs use a single ECT sensor in the thermostat housing for everything. OBD-I only used this for the aux fan and fuel mixture. The reason for the difference is most of the gauges in OBD-II are driven by the PCM via the Chrysler Collision Detection (CCD) bus. Oil pressure excluded as the PCM does not monitor this.