Frequently Asked Questions

ECU remapping optimises the software inside your car’s Engine Control Unit to improve power, torque, and fuel efficiency. At Mercia Remaps, every remap is custom-written to your vehicle, delivering sharper performance and smoother drivability.

Yes, ECU remapping is completely safe when performed by qualified professionals like our team at Mercia Remaps. We follow strict safety protocols and only work within your vehicle's safe operating parameters. Our Safety Measures: Comprehensive diagnostic testing before and after remapping Working within manufacturer safety limits Using professional-grade diagnostic equipment Creating backup files of your original ECU settings Thorough testing to ensure optimal performance Important: We never push your engine beyond its safe operating limits. Our goal is to optimize performance while maintaining reliability and longevity.

Many customers see noticeable fuel savings, especially on diesel vehicles, as the remap optimises fuel delivery and torque. With gentler driving, MPG improvements of 10–15% are common.

Depending on the make, model, and engine, gains of up to 30–40% more horsepower and torque are achievable. Use our Vehicle Lookup Tool to see the exact gains available for your car.

Most remaps take 1–2 hours from start to finish. We use dealer-level diagnostic tools to ensure everything is carried out safely and efficiently.

Yes. We keep a secure backup of your original ECU software and can return your vehicle to standard at any time if needed.

We serve drivers across Rugby, Coventry, Leicester, Northampton, Kettering, Loughborough, Warwick, Leamington Spa, and surrounding Midlands areas.

With over 15 years’ experience, certified technicians, the latest equipment, and hundreds of satisfied customers, we combine local expertise with proven results. Our focus is on safe, reliable power gains backed by friendly, professional service.