Modern vehicles have helpful tools or updates that can improve performance and fuel economy – one of them is engine remapping.
Carried out at a local garage, a mechanic can help remap a vehicle to the required specifications.
In this know how guide, we outline what it means, why it is something to consider, and its impact on your insurance.
What is engine remapping?
Engine remapping is a process, carried out by a qualified mechanic, where they modify a vehicle's Engine Control Unit (ECU) software to improve its performance and fuel efficiency.
The ECU is a small computer that controls various engine functions, including fuel injection, ignition timing, and turbo boost pressure. In higher spec vehicles, the ECU plays a crucial role in increasing performance.
By changing the ECU's parameters and limits, remapping can increase horsepower, torque, and 0-60mph speed times.
It does this by adjusting the fuel-to-air mix, along with timings and other performance variables. The result is faster acceleration and better throttle response. This is why remapping is often used in turbocharged engines.
In summary, remapping can be tailored to specific needs. For instance, some drivers prioritise high performance, while others might seek better fuel economy driving.
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Engine remapping impact on fuel economy
Remapping can improve fuel efficiency by optimising how fuel is burned.
Drivers may notice reduced fuel consumption as the remap adjusts engine function to operate more economically at certain speeds. It often helps maintain fuel economy at higher speeds – which is uncommon in most other vehicles.
One of the many benefits of remapping is that it can easily be reversed, meaning the ECU can be reset to its factory settings if the driver is not satisfied or it doesn’t meet the needs of the driver.
How to remap a car engine
Remapping a car engine requires a mechanic to connect a diagnostic tool or laptop to the car’s OBD (On-Board Diagnostics) port.
Once this has been done, the tuner uploads the new ECU settings. This is known as the ‘new map’, or software.
It overrides the factory settings with custom ones designed for specific outcomes. This includes power or fuel efficiency.
Engine remapping impact on a car's warranty
Before carrying out any remapping on a vehicle, it is important to consider how it would impact any warranty you may have.
In short, remapping may void vehicle warranties and could increase insurance costs.
It is important to consider that remapping may lead to increased emissions, which impacts road tax and emission standards.
Engine remapping impact on car insurance
Most car insurance providers require notification if an engine remap has been carried out. If you have an existing car insurance policy, you should notify the insurer before any work is done.
If you do not inform your insurance provider that your vehicle has been remapped then your policy could be invalidated.
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