The ECM, or Engine Control Module, is similar to the ECU in that it manages engine functions but is typically used in older vehicle models. It controls ignition timing, fuel injection, and emissions systems to keep the engine running smoothly. est In this article, we will break down the differences between ECU, PCM, and ECM, explaining their functions and how they affect your car's performance. Whether you're a seasoned car enthusiast or a new driver looking to learn more about your vehicl...