Here's a troubleshooting solution for the Crossfire EFI, a USB interface cable that plugs into the 12-pin OBD1 ALDL diagnostic port behind the ashtray and connects to a laptop USB port (I use WinXP):
ALDL OBD1 OBD cable OBDI OBD2 engine codes

If you upgrade the ECM to a 1227747 with a HAM module, you will need to use a serial port DB9 cable interface to your laptop as the HAM module will only work with a serial port, not USB.


I use WinALDL software to check the engine sensor voltages to see if they're up to snuff and within normal operating parameters:

http://winaldl.joby.se/

Anyone knows of another ALDL diagnostic program for the stock ECM 1225550 ?