ECU remapping

What is the Engine Control Unit (ECU)?

All modern cars and vans on the road today have an Engine Control Unit (ECU). The ECU can almost be described as the vehicle’s ‘brain’ and contains a processor that takes information from various sensors throughout the engine. It analyses information such as the engine temperature, accelerator pedal angle, oxygen content in the burnt exhaust gases, as well as many more parameters. Using the information from these sensors it can then add the right quantity of fuel at the right time to provide a good mix of fuel economy, performance and emission control when pulling away, overtaking, pottering down the road or zooming down the motorway.

What is ECU Remapping?

When a manufacturer develops a new car, they have to take into consideration all of the conditions it may be subjected to in all the regions of the world in which they intend to sell the model. This means that instead of optimising the ECU’s program, or ‘map’, to deliver the best performance or fuel efficiency, they have to make compromises to the map to take into account differing operating conditions.

These could include sub-standard fuels, extreme temperatures and altitude, differing emission laws and even the possibility that vehicle may not be serviced on a regular basis, in accordance with the manufacturers recommended instructions. An ECU remap takes a reading from the ECU’s processing chip of the vehicles standard compromised map and adjusts various parameters within the map. These include fuel pressure, boost pressure (on turbocharged applications), ignition advance and throttle pedal control, amongst others, to release the true performance from the engine. It is a completely safe process, as it is just allowing the engine to perform as it should have, before all the compromises were applied to the original programming.

Every engine has its own unique map.  By adjusting this we can fine-tune the characteristics of the engine; unleashing more power and in many cases reducing fuel consumption too. There are also different ways of mapping a vehicle. All petrol cars sold within Europe since 1st Jan 2001, and diesel cars manufactured from 2003, must have On-Board Diagnostic (OBD) systems to monitor engine emissions. These systems were introduced in line with European Directive 98/69/EC to monitor and reduce emissions from cars. However, OBD systems have been fitted to many vehicles since the early 1990s, and therefore OBD remapping can be carried out on many vehicles that were manufactured prior to the 2001 legislation.