ECU (Engine Control Unit): This is the brain of your car's engine management system, controlling various functions such as fuel injection, ignition timing, and emissions. Audi V8 PCM (Powertrain Control Module): A more advanced version of the ECU, the PCM oversees not only the engine but also the transmission, ensuring optimal performance of the powertrain. ECM (Engine Control Module): Similar to the ECU, the ECM focuses on engine-related functions, monitoring sensors and adjusting settings ...