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The Engine Control Module, or ECM, directly controls the engine. Still, it can’t do that properly without the Transmission Control Module or TCM and PCM, which work together and exchange information.

Did you use an OBD2 scanner on your car to figure out why the check engine light is on, only to get the P0303 code? Here's what it means, plus possible fixes.

What Does Code P0442 Mean? Engine code P0442 means a small leakage in the evaporative emission control system. It is not a critical problem, but it could be annoying and cause something more serious.

There are two key numbers you'll find on your car -- the VIN and the Engine number -- and both play key roles in your car's past and future.