Check Engine Light: A persistent check engine light could indicate a problem with the ECU, PCM, or ECM. Poor Performance: Decreased engine power, rough idling, or difficulty starting the vehicle may signal underlying issues. Erratic Behavior: Inconsistent fuel consumption, shifting patterns, or throttle response could point to control module problems. How to Diagnose and Repair ECU, PCM, and ECM Issues ...

Check Engine Light: A persistent check engine light could indicate a problem with the ECU, PCM, or ECM. Poor Performance: Decreased engine power, rough idling, or difficulty starting the vehicle may signal underlying issues. Erratic Behavior: Inconsistent fuel consumption, shifting patterns, or throttle response could point to control module problems. How to Diagnose and Repair ECU, PCM, and ECM Issues ...