car died, ran irratic when died, would sometimes start for a short period then die. scanned it and had several codes, swapped out all electrical sensors from a known good running vehicle, new knock sensor, new coilpacks, new icm, ecm, map sensor, throttle position sensor, got the trouble codes down to just one, code 43 (est error) how can i go about troubleshooting this to get the car running. the icm and coil packs are off a good running 94 3.1 lumina, does this engine have a different firing order, or something else different from the 92 regal 3.1. any help would be appreciated.