I recently purchased a perfectly running donor jeep to take all the good stuff 4.0, axles, top, doors etc. I got this jeep to replace all 2.5 stuff in a jeep inherited from my parents. Also perfectly running. I have completed the 4.0 swap into my parent’s old rig. It runs well.
With all the leftover parts I decided to put the 2.5 stuff into the old 4.0 tub to turn around a sell as a running jeep instead of parting it out. Now I currently have a no spark no start issue. Coil, cam sensor, crank sensor, relay are all good. Grounds are also good. It cranks over with no problem. Thought it could be the ECM so I changed the capacitors—still nothing. The harness looks to be in great shape.
I did notice an orange wire that was in the 2.5 Jeep that doesn’t seem to match the 4.0. It’s at the harness connection at the firewall above the valve cover.
Are engine wire harnesses for the 2.5 not compatible with the 4.0 tub harnesses or am I overthinking all of this and it’s something else?
With all the leftover parts I decided to put the 2.5 stuff into the old 4.0 tub to turn around a sell as a running jeep instead of parting it out. Now I currently have a no spark no start issue. Coil, cam sensor, crank sensor, relay are all good. Grounds are also good. It cranks over with no problem. Thought it could be the ECM so I changed the capacitors—still nothing. The harness looks to be in great shape.
I did notice an orange wire that was in the 2.5 Jeep that doesn’t seem to match the 4.0. It’s at the harness connection at the firewall above the valve cover.
Are engine wire harnesses for the 2.5 not compatible with the 4.0 tub harnesses or am I overthinking all of this and it’s something else?
