Ok, so I have some issues that I want to know if someone can help me with. I have a 1998 jeep cherokee that has the automatic in it and my parts jeep is a 1990 jeep cherokee with the ax15 in it. All of the mechanical stuff is in and hooked up, I have the transfercase from the 1998 paired with the ax15 from the 1990. When I turn the ignision, my volt guage and fuel guage does not work. I have the nutral safety switch jumped. When I turn the key the jeep will turn over but will not fire. I am using the computer from the automatic trans. I think something might be grounding out because the guage are not working but I do not know where. If it is not starting because the computer is not satisfied, how can I satisfy it. I know buying one for the year of jeep is the factory way but I don't have that option. If you have any CONSTRUCTIVE things that it could be I would gladly try then and get back with you if it did or didn't work. Thank you.

Which flywheel/flexplate did you use?

I used the flywheel in the 1990 jeep.

That flywheel is not compatible with the 1998 fuel injection system.

Why not? Isn't a flywheel a flywheel. I am also using the crank position sensor from the automatic, could that be a problem, and if so why. Not trying to be a d***, I just don't see it being a problem.

There are slots around the perimeter of the flywheel to trigger the CPS.
The slots are different between 90 and 98.
That's why it won't start.

ok, so swap the flywheel to a 98 and in theory it should fire up.

Yup.

Take the crank sensor out first. Those sensors are easily damaged should you bump them. One hit can kill them.

Here.

Excellent!!!

Wouldn't that CPS be problematic as well? Aren't the stick shift and automatic CPS part numbers different? (Assuming due to differences between the flywheel for an auto vs. stick.)

Nope, and nope. Strictly a year difference.

Interesting. So what's the difference between the 2? (In other words, why would the part number differ?) The connector maybe?

I don't know that.

I DO know the CPSs and flywheels between Renix and HO are incompatible.