I've got a 2003 2.4 that is blown up. I have a 98 4.0 with all accessories and complete engine harness as well as pcm. Have the new motor mounts and a ax-15. My question is will the 98 engine work in the 2003. The 98 4.0 is a distributor style motor. What electrical issues may I run into? Thanks
You'll need to weld new engine mounts on the frame, as the 4.0 has different engine mounts.
In addition, you'll need the engine and transmission from the 4.0, as well as the complete engine wiring harness, ECM, TCM, and maybe a few other parts I am forgetting.
In addition, you'll need the engine and transmission from the 4.0, as well as the complete engine wiring harness, ECM, TCM, and maybe a few other parts I am forgetting.
The other issue I believe you may run into I believe is the dash wiring. For the life of me, I can't find the thread, but @mrblaine I believe had mentioned differences in the dash wiring, and that your 2003 may have completely different wiring than that 1998 wiring harness, and therefore you may have to rip out all of the wiring behind the dash and in the tub.
I can't recall exactly what was said, but perhaps Blaine will chime in and set me straight. I need to make a sticky on this subject in all honesty, so the information would be good to have.
I can't recall exactly what was said, but perhaps Blaine will chime in and set me straight. I need to make a sticky on this subject in all honesty, so the information would be good to have.
There are only 2 years that have a separate TCM, 03 and 04. All years have a different PCM for manual or auto and 05 and 06 have the TCM incorporated into the PCM.
This is one we haven't done so I'm not 100% on the dash harness. My first thought is that it should work since I can't think of anything that is different between the 2.4 dash and the 4.0 dash except the OD off switch on the auto. If the engine harness will plug into the connector, I'd say you have a good shot at it working.
98 has 2 different harness plugs. you'll end up using the 98 computer and splicing wires if its an early 98 harness. The late 99 up are coil pack/opda instead of the distributor/plug wire.
We just did a 4 cyl to 6 swap in a 04. The donor rig was an 03, was plug n play. Some of the 6 cyl swaps are damn near the same work as an ls swap with wiring. The most challenging I've done was a manufacturer dated 2/96 4cyl to 6 swap with a 04 donor.
We just did a 4 cyl to 6 swap in a 04. The donor rig was an 03, was plug n play. Some of the 6 cyl swaps are damn near the same work as an ls swap with wiring. The most challenging I've done was a manufacturer dated 2/96 4cyl to 6 swap with a 04 donor.
Dave and I know you know this, the 00-04 use the camshaft synchronizer. 05-06 use the OPDA.
I can chime in here too. 97-02 use a 100 way connector above where your left knee would be. This is where all of the vehicle wiring “integrates” and is sent it’s separate ways. They changed that to a totally different style in 03 that makes it much harder to swap things.
In addition, 97-00 is CCD bus whereas 01-06 is PCI bus, so you would have to change gauge clusters. The radio is a different plug, as well as the HVAC controls, which are slide/cable style in 97-98 vs knob style in 99-06.
And speaking of that, you’ll have to convert your HVAC wiring to work with the knob style, otherwise you’ll need to get an HVAC box that works with the slide/cable style. And you’ll need to change out your dash too because the center portion where the radio and HVAC controls go is shaped different behind the bezel where it sits up against the HVAC box.
Like Chris said above, your best bet to make this work with your donor is to rip EVERY wiring harness off of the donor and put it in your 03. Engine, PDC, dash, and your rear wiring which is integrated with your fuse box harness too.
Unfortunately this is far from a plug and play swap. Even though the 4.0 is a Jeep engine, you’re essentially trying to swap in an engine that your specific Wrangler wasn’t designed for. It’s the same concept as trying to swap out the 4 cylinder motor in a Honda Accord for a V6 Honda motor which DID come in certain Accords. Eventually you could get all of the electronics to blend but it wouldn’t be an easy task.
In addition, 97-00 is CCD bus whereas 01-06 is PCI bus, so you would have to change gauge clusters. The radio is a different plug, as well as the HVAC controls, which are slide/cable style in 97-98 vs knob style in 99-06.
And speaking of that, you’ll have to convert your HVAC wiring to work with the knob style, otherwise you’ll need to get an HVAC box that works with the slide/cable style. And you’ll need to change out your dash too because the center portion where the radio and HVAC controls go is shaped different behind the bezel where it sits up against the HVAC box.
Like Chris said above, your best bet to make this work with your donor is to rip EVERY wiring harness off of the donor and put it in your 03. Engine, PDC, dash, and your rear wiring which is integrated with your fuse box harness too.
Unfortunately this is far from a plug and play swap. Even though the 4.0 is a Jeep engine, you’re essentially trying to swap in an engine that your specific Wrangler wasn’t designed for. It’s the same concept as trying to swap out the 4 cylinder motor in a Honda Accord for a V6 Honda motor which DID come in certain Accords. Eventually you could get all of the electronics to blend but it wouldn’t be an easy task.
I think I misread this as you had an entire 98 as a donor. If you just have the engine, the easiest option would probably be to get an engine harness and PCM that matches your year jeep. eBay or Davy’s Jeep is a good place to look. Fortunately the blocks are totally interchangeable, but you’d need a couple odds and ends like the camshaft synchronizer like David and Blaine mentioned above. I’m not sure what other sensors you would need to “change” due to model year. Hope this helps.
Great info guys. All this belongs in a big sticky thread, since the engine swap information is a very common topic.
So if I swap over all the sensors from a 03 4.0 and get a 03 4.0 harness it can be done without to much wiring complications?
Pretty much. I would double check the PCM pin outs just to be sure nothing is different between a 2.4 and a 4.0 harness. You’ll need an 03 PCM for a manual transmission too, or at least make sure it’s flashed for one.
IIRC, when researching V8 magnum swaps, the 5.2L PCMs could be flashed to run a 5.9L, and vise versa. So maybe you could have your 2.4 computer programmed for a 4.0. B&G performance would know.
Okay so my buddy has a 2000 DJ he is parting out and has a engine harness for a coil pack motor. Will this harness work in my 2003 tj with the 98 motor? I know I need to get a cam synchro unit but from there will i be all set?