i have a 93 trans am im stumped and need some tech help i swaped motors last fall and the car ran when it was put back together for bout 25 mins of driving i pulled the car in the yard got out and it started 2 cut off and then back fired tryed to start car back cut will not crank we have put hrs into researching what caused the problems we even put the car in a local shop and they couldnt fix it we have changed the coil the distributor ingnition module the ignition switch had a broke wire in the switch so we built the bypass module and got the theft mode lifted the only code that has showed up is 12 no reference pulses to ecm does anybody have any idea how to fix the problem and what the code means what else can i check to try and get the car to fire thanks for any info somebody might have