Wiring Harness then ECM
 

I own a 99 Bravada--In the last two years, I've had the front end rebuilt, new shocks & tires, rebuilt the transfer case, transmission, new AWD actuator motor.

My exhaust check valve malfunctioned, burning the RUBBER HOSE (?) on it thru, thus burning my wiring harness, leaving 4 or 5 wires burned in two, and MANY other wires to "re-insulate" with electrical tape.

But, after having that done, it won't shift, and it is still doing the "miss on 1 cylinder-there's a problem" trick.

Should I have to replace the ECM? Wiring harness? I've already replaced the O2 sensor & the vehicle movement sensor.

HELP! This has me stumped. I'm in this vehicle too deep to just scrap it.