Remapping, sometimes called ECU tuning, is when the settings of a car’s ‘engine control unit’ (ECU) is altered to improve several areas of the vehicle’s performance. By overwriting the existing settings with new software, the owner can re-programme the car to manage the fuel injection, airflow, sensors and more (within legal limitations).

Remapping a car changes the manufacturer’s default settings and software on the ECU, replacing it with new software which can be tweaked and customised to the owner’s specifications (within legal limitations).When a vehicle is remapped, the old ECU software is overwritten when the customised software is plugged in to the car’s serial port (sometimes referred to as an OBD port). This simple functionality has made the process of tuning a vehicle considerably easier, and has created many jobs for tuning engineers and specialist ECU software developers.

As mentioned above, remapping allows you to alter the performance of your vehicle by altering how the engine drives the car, however, it’s how the driver chooses to use the tuned car that ultimately decides what effects the ECU tuning will have.For example, it’s a common belief that remapping a vehicle has no effect on fuel economy, however, this technically isn’t true. As the result of ECU remapping, a car usually sees an increase in power, which can come at the expense of higher fuel consumption. Owners will often drive their cars more ‘enthusiastically’ after remapping, accelerating quicker when possible to enjoy the noticeable difference in output their car has, and therefore, further increasing fuel usage.On the other hand, if the driver chooses to change their driving habits to make the most of the increased power and torque throughout the ‘rev range’ and gear changes, then fuel economy can be improved. It really comes down to how the driver chooses to use the tuned car which decides how economic it becomes.Remapping a vehicle can also have an immediate effect on speed and power; in some cases, remappers claim to have increased horsepower by 30-40bhp, and torque up to 80nm!A car’s engine can also become more responsive, allowing the driver to overtake more easily. This can also cut down on the number of gear changes the driver has to make, allowing them to handle situations that require more torque without dropping down to lower gears. Again, this can help boost fuel economy if used strategically.

Many people might wonder ‘Is remapping a car good or bad?” As with all car modifications and maintenance, remapping a vehicle does come with risks and downsides, so it’s worth bearing these in mind before you decide to go ahead with the process.Firstly, it’s important to remember that not all cars can be remapped, usually due to their age. Typically, cars produced before 2000 are too old and don’t feature the car remapping software needed to optimise the vehicle’s performance.If you aren’t an expert in the industry it is not advisable to remap your own car. Choosing a reputable company to carry out the remapping is a good way to reduce the risk of anything going wrong.