Ecomotive ECD475 Clean Drive Fuel System Cleaner, 450mlDeposits build up throughout a fuel system over time, in the injectors, valves, DPF and other components, gradually costing power, efficiency and a clean MOT emissions result. Clean Drive is a fuel additive that goes straight into the tank, working through the whole system as you drive rather than requiring a workshop visit.Ecomotive had Clean Drive lab tested at the University of Leicester, using two engines on fixed-bed dynamometers to back up their improved fuel economy claims. The testing found measurable fuel economy gains. Ecomotive's own figures, based on that testing, are up to 15% better fuel efficiency and up to 60% lower harmful emissions, though results will vary by vehicle and how much deposit build-up there already is.Use it with at least a quarter tank of fuel: add the whole bottle, then drive as normal. Wait for the fuel warning light to come on before the next refuel, so the treated fuel has time to work through the system. For optimal efficiency, it is recommended one bottle every 3,000 miles for ongoing use.The advanced formula is designed to work with petrol, diesel and hybrid vehicles, rather than separate solutions. It is also worth using ahead of an MOT, since cleaner combustion can help with the emissions part of the test.