The 92-95 CPI 4.3's don't have the OBD headaches, as OBD2 didn't start until 95-96.

With OBD2 the electronics are fully integrated, and if you use the stock wiring harness, you need to supply the computer with everything from airbag sensors on down.

Prior to OBD2, the computer that controls the engine is stand alone. So mine ('94) has the GM engine computer behind the glove box with all the engine sensor, A/T wires, and speed sensor wires going out the wiring hole that's already there in the Mitsu. It's very convenient, as the Mitsu wiring (headlights, horn, power, etc) go out the driver's side fire wall. Almost totally seperate wiring.

The only GM-to-Mitsu/Mitsu-to-GM wiring that the 94 CPI "needed" is the tachometer pulse wire, the "check-engine" light, and the ignition. No big deal. I wired the GM check engine signal wire into the Mitsu gauge console to use the existing check engine light. You can read the GM codes with no trouble at all.

The GM ADL connector only uses 3 wires in 94, and is easy to use with a proper code reader, or even just a jumper wire and read the flashing code displayed on the check engine light.

I totally split the whole Mitsu wiring loom on mine, but only to let me get rid of the redundant wires. Since I re-wired fully the headlights and relay, and the horn (now an air horn), etc, many of the Mitsu wires were no doing anything any more. So I removed them fully. Then re-wrapped the loom to include my wiring changes. Tidy.