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What Does an ECU do in Your Car?

The engine computer is one of the most important components of any modern vehicle, but as cars become more advanced, the engine control module is becoming more important than ever. In recent years, companies have begun developing vehicles that contain more sophisticated engines and these advances have enabled companies to support the growing demand for more innovative vehicles. Most of us get in our car and trust it to run smoothly, in fact, most of us don’t even think about its internal control system unless something goes wrong; so what exactly goes on under the hood of our car? While this may seem insignificant, knowing how the engine management system works may save you a ton of headache and even more money if something were to go wrong.

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So what is the engine computer? In simple terms, the engine control unit (or Electronic Control Module / Electronic Control Units ) is the “brain” of your vehicle, in that it controls and is the center of the engine management system. In short, it controls the way your vehicle runs ,it’s idle speeds and your electrical system; it ensures that your vehicle is running properly and efficiently. The fuel economy and the way your vehicle performs are both controlled by the engine control module and if it’s not functioning correctly, then your vehicle will not run correctly, or, at times, run at all. Sensors and actuators are in constant communication with the engine control unit. The computer receives data from individual sensors that tell the computer how the vehicle is running. The computer will then analyze and interpret this data, and in turn, send a signal to a variety of actuators which will allow them to adjust their performance based on what the computer determines the vehicle needs.

For example, if the engine is running too rich, then the oxygen sensors will communicate this to the computer and, as a result, the computer will determine the amount of fuel that needs to be supplied by the fuel injection system based on these conditions. This is how the engine computer is responsible for the fuel economy in your vehicle. If you are experiencing a reduction in fuel economy, then it may be because there is a problem with the amount of fuel being injected by the fuel injection system. Because the engine control unit is constantly working by receiving data and transmitting signals, it learns the drivers habits and adjusts itself accordingly which allows it to get the best possible performance out of your vehicle.

In addition to controlling the way your vehicle operates, the engine control unit is also responsible for assisting with diagnostics. When the warning light comes on in your vehicle, that is the ECM alerting you of a possible problem and that auto repair will be required. For example, if your car won’t start then you can check to see if the check engine light is on. That light is always accompanied by a series of fault codes that you can then assess to determine where the problem lies.

The condition of your engine computer and the condition of the electrical system is critical to the overall condition of your vehicle and it is worthwhile to understand the basic mechanics of your Electronic control units as cars become more advanced. An engine computer is one of the more costly replacements should your vehicle ever need one, so being mindful and aware of the way your vehicle is running could benefit you in the future.


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