What Does Code U0100 Mean? U0100 stands for “Lost Communication with ECM/PCM.” The Engine Control Module (ECM) is the computer responsible for controlling the engine. The ECM communicates with other ...

Consumer Reports explains what the check engine light means and what to do when you see it: how to tell if your car has a loose gas cap—or a serious engine problem.

A check-engine light could be a gentle reminder or a sign of something catastrophic. We explain what a malfunction indicator light is and what you can do about it.

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.

Did your vehicle's check-engine light just pop on? An OBD-II scanner can provide some direction. We tested a handful to find ...

If you see the check engine light and haven’t filled up with fuel recently, it’s a good idea to use a code reader or take your vehicle to a shop for diagnosis.

Looking for information on how to check the engine size by your VIN. Check out the Drive’s guide to check your car’s engine size by its VIN.

CarMD.com, a provider of automotive diagnostic data, reported 675 different possible reasons for a check engine light to come on.

Remember, the code reader won't tell you how to fix the check engine light—the code it reads just directs you to the fault. From there, unleash your mechanical prowess and discover the cause!