Bought an 94 grand am gt V6 3100 with 122k miles, wont start. Have spark, but injectors are not getting ground signal from ECU. Can spray starting fluid into air box, and it will start and run as long as keep spraying fluid in. Injectors are getting 12v, but no ground signal. Put scan tool, generates no codes. Have spare ECU, but same results. Have replaced map sensor. Looking at wiring diagram, unable to determine if cam sensor or crank sensor provide info to ECU for Injector signal. Have replaced bad fuel pump and filter, getting good fuel pressure to injectors. All fuses and grounds are good. Any help appreciated. Past owner said engine was running fine, drove to store, came out, hasnt started since.

too little miles to die, without looking at the wiring I can't tell if the ecu proves ground or 12+ for the injectors but I'd check the wire path of the ground to make sure something isn't unplugged or corroded. Crank sensor is for ignition and cam sensor is for fuel for the most part. Dunno if any of this helps but I'd start with tracing the wires, good luck troubleshooting.