ECU Mapping
 

What is an ECU?

An engine control unit (ECU) is a computer that runs the engine in all modern day vehicles, Introduced in the early 1980s with the advent of electronic fuel injection systems, these early systems where very primitive and they just monitored the revolution of the engine, air flow into the engine and engine temperature. The ECU then used this information gathered from these sensors to inject the right amount of fuel at the right time. The advantages of fuel injection over a carburettor based engine was the degree of control that a computer had over fuel delivery, 1000’s of times more accurate than that of a carburettor.  ECU’s determine the quantity of fuel, ignition timing and other parameters by monitoring the engine through sensors. More advanced ECU’s found on most modern cars, vans and trucks also control the ignition timing, variable valve timing (VVT), Manifold Absolute Pressure (MAP) sensor, throttle position sensor, air temperature sensor, oxygen sensor, the level of boost maintained by the turbocharger (in turbocharged cars, vans and trucks), and many other peripherals. Often this monitoring and control is done using a control loop such as a proportional-integral-derivative controller (PID controller). Before ECU’s, fuel injection, ignition timing, and idle speed were directly controlled by mechanical and pneumatic sensors.  In the present day an ECU is a very powerful control system capable of gathering hundreds of channels of information to control every aspect of the engine, even its own efficiency.  Ironically, the worse place in the world that you could put a sophisticated piece of electronics is under the bonnet of a car or truck due to massive vibration, constant heat variations and intense radio interference from ignition systems added to the fact that the manufacturers must produce on a huge scale.