I must have a dozen ECU's for mopars I use Pertronix now or point dist Sick of chasing the Mopar ghost of no start usually due to pickup plate -ECU or bad ground My truck did the same thing backfired and quit turns out it was ground to ECU or should i say rusted away ground.

By the way if you stay with Mopar get a new box just a stock one or a echlin NAPA