I want to remap my car's electronic control unit — what do I need to know?

Your motoring questions answered


I am considering tuning my Audi by remapping the electronic control unit (ECU), but several people have told me that when the vehicle goes in for servicing, any changes can be wiped by the computers at the dealership. Is this true?

Q. I am considering tuning my Audi by remapping the electronic control unit (ECU), but several people have told me that when the vehicle goes in for servicing, any changes can be wiped by the computers at the dealership. Is this true? AM, Hastings


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A. If carried out correctly, an ECU remap can improve drivability, performance and fuel economy. There are other matters to consider, though. First, if your car is under a manufacturer’s warranty then you would almost certainly find it invalidated should anything untoward happen with the engine after you have tuned it.

Second, you must inform your insurer of the modification. Some will accept a change with little or no difference to the premium, others will increase your payments and some won’t accept ECU modifications at all. (Several tuning companies can supply details of insurers that look favourably on this form of upgrade.)

Finally, Audi tells us that if your ECU needs an update during a service this will wipe whatever modifications have been made. There are ways to restore the tuning, however. Superchips (superchips.co.uk), a remapping specialist based in Buckingham and with more than 80 centres nationwide, said it could reinstall a remap free of charge.

Individual dealers could make a charge at their discretion, and AmD Tuning (amdtuning.com) in West Thurrock, Essex, said it could rewrite its remap for any new software for £72.

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