Your A to Z of motoring gobbledygook
Variable valve timing (VVT)
Valves let fuel and air in and out of the engine's cylinders. In most cars, the timing of the valves' opening is fixed to offer a fair compromise across the whole rev range. VVT, however, adjusts the timing with the speed of the engine so that it is always working at its peak efficiency.
VIN (Vehicle Identification Number)
Vehicle Identification Number. This is the manufacturer's own ID, found under the bonnet, under the carpet by the driver's seat and/or etched on to the windows. You will also find it stamped onto a plate, either under the bonnet or in one of the door openings. Some cars have 'visible VINs' behind their windscreens. Vehicles which are approved for sale in the EU have 17 digit VINs.
VRM
Vehicle Registration Mark, or number plate.
