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Car remapping improves your vehicle’s performance by modifying its on-board computer’s programming to alter various engine settings.
Engine remapping can be a cost-effective way to get the most out of your car. This type of modification can make your vehicle easier to drive and improve your engine’s fuel efficiency.
But remapping can make it harder and more expensive for you to get car insurance quotes because insurers think of remapping as a vehicle modification. Some companies don’t insure remapped cars at all. Other providers charge higher premiums. It’s important to note that if you have your car remapped, its warranty is likely to become invalid.
This guide tells you everything you need to know about the benefits and costs of remapping your car and explains the impact that remapping can have on your car insurance.
Car remapping involves altering the settings of a car’s electronic control unit (ECU), which is also referred to as an engine control unit. Here are three other names for remapping:
Remapping should only be done by a professional who uses specialist software and diagnostic tools. You can take your car to a local garage to get it remapped, or you can have a mobile car remapping service come to your home or workplace to do the job.
Make sure you find a reputable business to remap your car. Some remapping specialists have been certified by the Institute of the Motor Industry.
You should never let an amateur attempt to remap your car. Doing it wrong could damage your car, invalidate your car warranty and void your car insurance.
Your car’s ECU comes with its own preset configuration that limits its performance capabilities. The remapping process overwrites this configuration.
Remapping can improve your car’s throttle and engine response and result in increased fuel economy. You can have your car remapped to enable it to go faster and perform well at high altitudes.
Modern technology makes it possible to overwrite the ECU chip inside your vehicle by plugging a laptop or handset into the car’s on-board diagnostics port, but not every car can be remapped in this manner.
For example, modifying ECU chips in vehicles made before the year 2000 involves manually removing them and retuning them or replacing them with new ones. Some current-day manufacturers lock the chips in their cars to prevent remapping.
The types of cars that are most commonly remapped have turbo diesel engines with TDI, HDi or CDTi designations. Remapping these cars generally achieves the biggest performance improvements for a relatively low cost, but most modern cars with petrol engines can also be remapped.
The advantages of remapping your car can include:
The disadvantages of remapping your car can include:
Car remapping normally costs between £200 and £400.
Several factors impact the cost of remapping your car:
Remapping costs around £1,000 if it includes the use of new parts, such as air filters or an exhaust. If the job includes extensive changes to your car’s engine, you could wind up paying thousands of pounds.
Many professional remappers will give you personalised online quotes for remapping your car.
Insurance companies consider engine remapping to be a modification. They generally charge higher premiums for modified vehicles.
When you generate a car insurance quote, you’ll be asked if your car has been modified. If you have had your car remapped, you should answer “yes”.
The insurer or price comparison site will then ask for details about the modifications. Remapping typically falls under a category that is labelled “engine” or “engine and transmissions”.
The options include various increases to brake horsepower, which takes the friction between your car’s tyres and the road into account when measuring the power your engine generates. Other options focus on transmission changes, turbocharging and issues such as whether the engine has been bored out or replaced.
To obtain accurate insurance quotes, you must be honest and precise about the extent of the remapping you have had done. When you improve your vehicle’s performance, you make it a higher-risk car and increase the insurer’s risk.
If you have car insurance before you get your car remapped, you must tell your insurer about the remapping after the job has been completed. If you fail to inform your insurer about remapping or other modifications, your policy could be invalidated. This could result in the rejection of any claims that are made.
Insurers usually increase the premiums for remapped cars. Some insurers refuse to provide coverage for them. If you need to look elsewhere for cover, be sure to get quotes from specialist insurers that provide modified car insurance.
If you’ve had your vehicle remapped, you need to notify the Driver and Vehicle Licensing Agency (DVLA) by updating the V5C log book the agency issued when your car was registered in the UK.
In general, you must update your V5C whenever you change your vehicle’s colour, engine, cylinder capacity, fuel type, seating capacity, vehicle identification number or wheel plan.
You must give the DVLA evidence, such as a receipt, an inspection report or a letter from the garage, that confirms you made changes to your car. The agency will inform you if you need to have your car inspected.
Remapping is usually safe if a qualified, experienced professional uses the right equipment to do it, but increasing your engine’s power may impact your car’s reliability because it adds stress to your engine.
It’s not a good idea for amateurs to try to remap their cars by following instructions they find online. DIY remaps can go wrong and damage car engines.
When you buy a car, you should ask the seller if it’s been remapped. If you don’t trust them to answer truthfully, you can pay a remapping company to examine the ECU with specialist technology.
When you sell your car, you should tell your buyer if you’ve remapped it. Your buyer needs to know about the modifications you’ve made to it so they can get the right car insurance.
You should give the buyer documentation that provides information about the remap, including the remapping specialist’s name, the remap date and the ECU settings’ changes.
As was previously mentioned, you should include the remapping details in your car’s V5C log book. The new log book the DVLA sends the buyer will include that information.
If you drive a leased car, you’ll need the leasing company’s permission to make any type of modification, including remapping. Most companies allow you to remap their vehicles if you can reverse the changes when your lease ends.
If you don’t ask your leasing company whether you can remap your car, you could have your car warranty invalidated or be penalised when you return the vehicle by having to cover the costs of returning it to its original condition.
