I'm glad it's not vtec, it makes troubleshooting a little easier at least...

Th PM6 is an OBD0 computer, and you have an OBD1 engine? Care to explain a little more about the wiring swap

My next instinct kinda tells me it's a sensor on the distributor that is wired squirrely. And what qtiger said is DEAD ON about performance roms disabling diagnostics.

Open up the ecu, and see if there are any 42 pin chips with like a sticker over them, that'll tell you if it is fact chipped.

But yeah, more info on what's up with the wiring.

-PHiZ