I bought the Jeep with 90k miles on it and a motor with a bad rod and major engine noise. The engine ran and drove but very loudly and dangerously. The only reason I state that is that I know the computer and all components were fine because it would start right up, run, and drive...just made a LOT of racket.
I bought a used motor from a guy who was about to do an engine swap to a 4.3 conversion. I heard his 1993 motor run. I helped him pull the motor and I took it to my place to replace my 1994 2.5. I just did the swap of the 1993 YJ 2.5 into my 1994 YJ that had a 2.5. After making the switch, I don't have any check engine light and I don't have an power to the starter. If I bypass the relays and give power from the ignition switch to the starter, I don't get any fire at the coil so there's obviously a computer or crank position sensor issue. I put in a new CPS but no change. I swapped computers so I put the 1993 computer in...again, no change. One of my questions is if I changed out the engine (should be identical), do I need to change out the computer to match it or does the computer match the vehicle more than the engine? The sensors all seemed to line up with the engine wiring harness. The vehicles were the same config (2.5 w/ manual transmission and no options...both S models) so this should have been an easy swap. Help!
I get the battery light when I turn the key ahead to the start position, but I have no check engine light when the key is in any position. When I try this without any computer or CPS in the vehicle, I get the exact same symptoms. I can trouble-shoot with the best of them but this is killing me. For what should have been a 4-6 hour engine swap and go, this has consumed several days of my time.
Any help would be highly appreciated.