When your car's ECU, PCM, or ECM malfunctions, it can manifest in various ways, affecting performance and drivability. Here are some common issues to watch out for and troubleshooting tips to help you address them: The Powertrain Control Module (PCM) and Engine Control Module (ECM) are terms often used interchangeably, but they serve distinct purposes. The PCM oversees not only the engine but also the transmission system, integrating multiple control modules into a unified unit. On the other ...