mapping faqs


How much money can I save by improving my fuel economy?

Fuel saving works best for diesel vehicles - so it depends on your vehicle type, the upgrade you chose, your driving style and how often you drive.  We offer a wealth of advice on how to save money as a motorist via our Money-Saving Motoring research website. If you have a diesel vehicle, we can arrange for a bespoke eco-map that would typically save you 10 - 15%. For commercial vehicle managers/owners the savings can be huge.  The VIEZU system helped one customer save 15% of a £20,000 a month fuel bill - that’s saving of £36,000 a year. Why not submit your car details for an estimate on your saving?


How much extra horsepower can you give me?

It depends on your vehicle and what your starting point is.  We recently gave a VW van an extra 76 brake horsepower - allowing the owner to enjoy towing his caravan! Why not submit your car details for an estimate on performance.


How long will it take?

The upgrade takes a few hours and we usually book in slots for either the morning or afternoon.


My vehicle has failed an MOT on emissions, how can you help?

An engine clean and an eco-map can help significantly - please get in touch and we will work with your garage to try to help.


My car has a fault or warning light on it, is it still safe to improve, using your system?

It really depends what the warning light is for. The most important thing is that your engine is healthy.  We run a diagnostic report prior to an upgrade that should flag up anything wrong - but if you know there is a problem, it should be fixed first. We would never proceed with an upgrade without discussing it with you first, in this instance.


Do I have to have the engine cleaned first?

You don’t have to, particularly if it is a very new car.  We have upgraded vehicles that haven’t been cleaned. The results are better when we map a clean engine, as opposed to an old dirty engine.


Is this upgrade tried and tested?  Is it safe?

Miles Better are VIEZU approved dealers and as such we are fully insured. VIEZU is an ISO registered organisation, which has been registered with the British Standards Institute since 2011, it has worked on over 100,000 engines in sixty-eight countries across the world - including the 24,000 strong BT fleet.  VIEZU is the first engine upgrade system to win the Queen’s Award for Enterprise (2015,) in recognition of their Fuel Saving Tuning Solutions, Carbon Emissions Reduction, and Software Development.


Do I need to tell my insurance company?  Will my insurance increase?

We always recommend notifying your insurance company. In most cases, especially with eco-mapping, your premium won’t increase. We have always notified our insurance company whenever we have upgraded our vehicles and the premiums haven’t gone up.  Why not call them in advance, to ask if it will make a difference and to put your mind at rest?


What if my vehicle develops a fault once you have worked on it?

The VIEZU system will not cause your vehicle to develop a fault. Our maps are fully insured. If your car develops a fault that is found by an independent inspection to have been caused by the upgrade, you will be covered by our insurance.


Would this upgrade affect my manufacturer's warranty?

No. Our engine maps cannot completely invalidate a vehicle’s warranty. Manufacturers do of course have a right to investigate and reject a warranty claim if they believe a failure is directly related to, and or caused by the upgrade. VIEZU technology is insured, so if our upgrade directly causes a failure - inside or outside of the warranty period - we have insurance in place to support you. Some customers do request us to have their maps reset to stock values at the time of a service or a warranty defect. If you would like your car reset, we will be happy to assist. However, this is not really a necessity. If your upgrade is over written by a dealer update, don’t worry, we can re-apply the tune for you free of charge for the lifetime you own the vehicle.


Are lease companies happy for me to do this on a lease car?

Many drivers of lease cars have them mapped - some choose to tell their leasing provider, others would rather not say; either way we would recommend the upgrade is removed before the vehicle is returned. Providing the vehicle was originally  mapped by us, we will be happy to remove it at the end of your contract or lease period, free of charge.


I can’t come to you - do you offer a mobile service?

We can offer a mobile service if you have a good wireless internet connection and a power supply that we are able to use.  If you are more than 25 miles from us in Gloucestershire, we may also charge a mileage and call-out fee. Please get in touch to arrange this.


What does the process actually involve? How does it work?

It is actually very simple and not dissimilar to updating your mobile phone. Modern engines are electronically controlled by a range of sensors. These sensors send signals to an on-board computer (called an ECU), which uses the data to make rapid and continuous adjustments to suit the varying conditions as you drive.  We use a specialist tool to read your car’s software data. This is examined by our VIEZU-approved technicians and used to produce a bespoke upgrade file, which is then uploaded back to your car.  The modified software optimises how the ECU uses data from the sensors, delivering results that are otherwise unobtainable. Manufacturers use the same programming technology themselves when offering new, higher specification models of their own vehicles – often with a significantly higher price tag!


How much does it cost?

Depending on a number of factors, the price can vary between about £200 and £450.  If you submit your car details to us, we aim to give you a price within two hours.


Is it legal?

Yes it is! Our eco-maps will actually help your vehicle to meet legal emissions standards. Of course, if you are increasing the power of your vehicle, it makes sense to ensure that everything is in good working order, and that your insurance company has been informed.


What if I don’t want the upgrade any more?

We can remove the upgrade and return the vehicle to exactly how it was before. If for any reason you are not happy with the upgrade, we offer a 30-day money back guarantee and a return to standard settings.


What type of vehicle or model of car be upgraded? Does it matter if my engine is petrol or diesel?

We can work on most vehicles built after the year 2000.  Eco-mapping works best for diesel cars and there are a wide range of vehicles that would benefit from a performance upgrade.  Why not submit your details for a free estimate of cost, fuel-saving, torque and horsepower increase?


Is my car too old or too new to have an upgrade?

We can work on most vehicles built after the year 2000.   Generally, the newer the car, the better the result.


What is the difference between your upgrades and mapping, tuning or chipping?

Ever since mass-produced vehicles began using sophisticated computers to manage how their engines operate, engineers have worked to improve and optimise their programming. In the early days, the Electronic Control Unit (ECU) was often a single computer chip, which led to the term "chipping" when referring to changing or swapping the chip for a reprogrammed one.

The term tuning dates back even further and literally refers to the frequency of vibration in the exhaust system, which produces a sound or note that can be altered (tuned - like a musical instrument) to optimise how it functions. Tuning nowadays is a catch-all term that encompasses any activity designed to enhance the performance or efficiency of the engine.

The term mapping brings things more up to date. A map is the software file running in the modern (highly sophisticated) computer - or computers - that control how today's engines run. They monitor and manage thousands of different parameters, enabling your vehicle to run correctly. When a vehicle is "mapped" or "re-mapped", it means that the software is examined and adjusted to optimise a wide variety of settings, providing more performance and/or better fuel efficiency.