The world's most complete luxury 4x4 just got smarter, with the 2007 model year Range Rover TDV8, on sale this week in the UK, pioneering an innovative world-first technical solution – the petrol fuel guard system.

The petrol fuel guard system helps prevent drivers filling their diesel vehicle with petrol – an increasingly common error in this age of the ultra-refined diesel engine.  Land Rover's innovative new system is incorporated into the vehicle's diesel filler head and automatically activates the intervention of a mechanical shutter if a petrol nozzle is inserted, preventing petrol being dispensed into the diesel tank.

The system distinguishes between petrol and diesel nozzles because thinner unleaded petrol dispensers go deeper down the neck of the vehicle's fuel tank, activating the shutter.

Chief programme engineer for the 2007 model year Range Rover, Paul Walker, says: "The new TDV8 engine in the Range Rover is so powerful and refined we feel that there is a danger, more so with this vehicle than with any we have sold in the past, of the driver mistaking the vehicle for a petrol-powered derivative – especially if the driver isn't the vehicle's regular user.  Mis-fuelling is an expensive and complex problem to fix, and we are delighted to be first to the market with this innovative solution."

The UK's Automobile Association reports that in 2005, over 100,000 cases of mis-fuelling were reported, with diesel vehicles being filled with petrol in error. The associated costs are significant, often amounting to several thousand pounds if the incorrect fuel enters the engine upon starting the vehicle.