Is there a difference between the DOHC and SOHC engine controllers? What about ATX and MTX?
The powertrain control module, or PCM, is unique to a given model year and engine type. Actually, from ’96 up, the unit itself is interchangeable; however, the programming is engine- and year-specific. Each type carries a different part number, which refers to the correct software flashed into the EEPROM chip inside. There is little advantage to be gained by swapping controllers between engine types, anyway. The Neon engine will run with the wrong controller, but not very well. The cam timing is quite different between the two engines, which means the fuel ratio table for one engine is not well suited to the other. The ACR engine controller, contrary to some rumors, is not substantially different than the corresponding type/year from a regular Neon. The only change is adjustment/deletion of the speed limiter. The important things such as spark timing and fuel ratios are identical. While there are some differences between the ATX and MTX controllers, none affect the power out put of eit
The powertrain control module, or PCM, is unique to a given model year and engine type. Actually, from ’96 up, the unit itself is interchangeable; however, the programming is engine- and year-specific. Each type carries a different part number, which refers to the correct software flashed into the EEPROM chip inside. There is little advantage to be gained by swapping controllers between engine types, anyway. The Neon engine will run with the wrong controller, but not very well. The cam timing is quite different between the two engines, which means the fuel ratio table for one engine is not well suited to the other. The ACR engine controller, contrary to some rumors, is not substantially different than the corresponding type/year from a regular Neon. The only change is adjustment/deletion of the speed limiter. The important things such as spark timing and fuel ratios are identical. While there are some differences between the ATX and MTX controllers, none affect the power out put of eit
