All about

Engine Management Systems

All about

Engine Management Systems

General information

To ensure a vehicle performs reliably, it’s essential its engine management system (EMS) is engineered to a high degree of accuracy. To guarantee a superior level of performance, DENSO has been working for many years to advance the design of our engine systems and components and develop innovative technologies that lead the automotive market in terms of fuel efficiency, lower emissions and high engine output.

DENSO car parts and pioneering EMS technologies are designed to improve vehicle efficiency. They include Exhaust Gas Recirculation (EGR) Valves, plug-in Mass Air Flow meters and adding quantitative measurements to Lambda Sensors, all of which were world firsts in the market. Integrating an EGR valve with an air intake throttle valve improved the emissions performance of diesel engines in a more compact design. When inserted into an intake pipe wall, plug-in Mass Air Flow meters helped to reduce vehicle weight and make installation easier. Finally, adding quantitative measurements into Lambda Sensors enabled greater accuracy in detecting air and fuel mixture levels, enhancing ignition performance.

Combining our many years of experience in the global car market, precision engineering, advanced design and the highest OE quality, we’ve developed a pioneering EMS range that is now available to the aftermarket.

Check out the new Engine management system movie.

Installation and fault finding

Effective engine management and engine control systems are central to a vehicle’s performance. To ensure you install DENSO's precisely engineered systems and parts correctly and find any faults quickly and easily, take a look at the download section.


What is an engine management system?
An engine management system (EMS) is a self-contained, custom-built computer. It controls the running of an engine by monitoring the engine speed, load, and temperature. It also provides the ignition spark at the right time for the prevailing conditions and metering the fuel to the engine in the precise amount required.
What components make up an EMS?
A system for engine management consists of a broad range of electrical and electronic components. These include sensors, relays, actuators, and an engine control unit (ECU). These parts work harmoniously to provide the system with critical data parameters essential for governing various engine functions.
What is an engine control unit (ECU)?
Also known as an electronic control module (ECM), an ECU's principal job is to keep the engine running smoothly. An ECU controls the quantity of fuel entering the engine's cylinders on cars fitted with electronic fuel injection. This optimises the fuel-air mix in the cylinder when it's compressed, maximising the car's power and reducing the amount of fuel wasted.
Where can I find the ECU in my car?
There is no industry standard for positioning ECUs, so their location varies depending on the car's make and model. However, it is generally close to the engine, so it will probably be found in the engine bay or somewhere to the front of the car's interior, such as under the dashboard or in the glove box. The precise position of the ECU should be listed in the owner's manual.

Catalogues and marketing materials

To find out more about Engine Management Systems browse the Downloads Area section. Click here.