94 to 99 engine swap

I have a 94 4.0 auto that is rusted out and I'm looking at buying a 99 4.0 with a blown motor. I have experience putting a 94 motor into an 89 so I am well aware of what the job calls for, however I'm not sure of the compatibility of the sensors and what not. I'm fairly certain the head on the 99 is cracked so I won't be able to use the 94 block with the 99 head. Any suggestions or information would be greatly appreciated.

I say we dump the whole thing in there and swap the sensors over.

I think thats all we need to do man.

All the exhaust special crap will be in the 99.

Might have to take the dizzy and flex plate, cuz the 99 is coil pack Im sure it wont be too bad.

if you are serious about it I can give you the info to swap it in, fairly simple

I am very serious about doing the swap. All I'm waiting on is getting the PO of the 99 to sell it to me. Like I said Stockli and I swapped a 94 into an 89 so I know what I'm getting into for the most part. Not to mention we did it in the middle of winter on a sloped driveway.

PM sent

The sensors on the 99 engine are all different from the sensors on the 94 and will have to be moved to the donor engine.

Ignition coil and distributor will also need to be swapped, since the internal electronics are different as are the connectors.

The injectors also have different flow rates so they need to be moved too. You also need to keep the fuel rail on the 99 and move it over to the 94 donor since the fuel line plumbing is different.

You can use the 99 intake manifold (curved) but if you move it to the 94 you will also need to move the power steering pump and bracket since the mounting was changed. The 99 setup is much better all around so I recommend doing this.

Just to clarify you are saying that I need to keep the 99 injectors correct? I had already planned on keeping the 99 intake and taking as many of the acessories as possible. As far as the dizzy goes I was under the impression that 99 is when they went to the distributorless ignition set up. If this is true do you have any suggestions on how to block off the dizzy hole in the 94 block or will that be used by something in the 99 setup? Thank you much for the responses you all are a great help in helping me understand what is needed for this conversion.

Install the 1999 intake/exhaust manifolds, distributor, belt driven accessories, OBD-II sensors, and flywheel onto any 1991-2001 engine block.

If the head is cracked, you will need to replace it. Use your Google-fu and do the search thingy, you may be able to use the 94 head in an OBD-II Cherokee. The 1991-95 7120 head and 1996-99 0630 head should interchange.

Awesome andthank you guys for all the help.

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DrShaggford said:

Just to clarify you are saying that I need to keep the 99 injectors correct?

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yes you have to use the 99 injectors with the 99 computer, since the computer is programmed to use a specific pulse width

As far as the dizzy goes I was under the impression that 99 is when they went to the distributorless ignition set up.

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no, the 99 still has a distributor... coil packs were introduced in 2000