Re: '99 4.0 has '03 ECM in it. Swapping back to '99 ECM & I have questions
You made the right call consulting help from an ASE mechanic. Computers are a pain in the ass to deal with on vehicles, since they're a major component in an automotive system. It takes special training to understand them, and most of us here don't have that kind of knowledge. The only true people that can help are those that have knowledge in automotive computer systems, and most of the guys that have that knowledge here lead busy lives fixing these computers for everybody else, and don't have much time to get on here. Either way, good luck, hopefully you can get this figured out.