The engine control unit (ECU) is basically a computer that controls how the engine works, a bit like a brain.

But the default settings – or maps – are not necessarily the best they could be, as manufacturers who sell their cars around the world have to take into account different climates, fuel qualities and laws when they program the software.

Car makers are also known deliberately to limit the performance of their cars through the ECU so they can release faster models at a later date, with just a few software changes and a much higher price tag

Remapping is intended to make the most of your car by overwriting the ECU’s default settings with new software which can be programmed to enhance the car’s overall performance.

It usually takes between 1-4 hours, and modern technology means it’s pretty straightforward.

Previously, the process was called ‘chipping’ and involved the removal of the main microchip from the ECU, which was then replaced with a modified chip. But now with new technology plugging in through the OBD or diagnostic port this is don without having to open up any ecu less chance of any damage.