Engine Control Module (ECM)
WARNING: This page is about a different car, the 2007 Saturn Ion 3 and 2007 Saturn Ion 2. However, it is still accessible from the selected car via links, so may be relevant.
The engine control module (ECM) controls all ignition system functions, and constantly corrects the spark timing. The ECM monitors information from various sensor inputs that include the following:
- The throttle position (TP) sensor
- The engine coolant temperature (ECT) sensor
- The mass air flow (MAF) sensor
- The intake air temperature (IAT) sensor
- The vehicle speed sensor (VSS)
- The engine knock sensor (KS)
- The manifold absolute pressure (MAP) sensor