What it does

Most modern cars contain an Engine Control Unit (ECU) that is, in essence, a tiny computer that controls how the engine operates. Vehicle manufacturers de-tune engines by setting the ECU to ‘default’ mode before sending your car to the forecourt. This ensures your vehicle meets EU regulation on emissions and power outputs.


When you remap a car, you replace the default programme installed on the ECU. The new programme will have been optimised by maximising the vehicles overall performance. This is known as ‘remapping’, as the ECU is essentially a program that controls how the engine works. When your car is remapped, the updated software is transferred via the serial port (also known as an OBD port) which then overwrites the engine map with the new enhanced version.


Originally, ECU Remapping was defined as ‘Chip Tuning’. This method required the removal of the Eprom from the ECU and the software is programmed directly in to the chip. Chip tuning or ‘chipping’ has become less and less popular in the market, as OBD remapping, requiring no removal of the ECU, has replaced it.


You’ll hear many people say that ECU remapping doesn’t have an affect on fuel consumption, however, this isn’t true. Because of the process involved in ECU remapping, more fuel is going to be consumed in order to increase the overall power. If the car is driven with a heavy right foot, after the remap has been completed, then fuel economy is unlikely to increase. However, if the driver modifies their driving style, making the most of the additional power now available, then fuel economy can be increased by improved torque and high rev ranges.

In general, after remapping, the driver no longer has to drop down gears to maintain speed on an incline and they may not have to change gear as frequently in traffic. This is where improved fuel economy will become noticeable.


There’s a wide range of reasons to choose to remap your vehicle. Firstly, you’ll notice that your engine responds better when the accelerator is pressed. The overall torque and power will be noticeably increased and power delivery will be smoother, making for a more enjoyable driving experience.

During normal, light driving, you’ll notice that your MPG is better, leading to cost savings overall, if the vehicle is driven carefully