Saving petrol devices

[Blueboy]

Hello 

Fellow Vauxhall Corsa owners .

Have you heard of a plug in chip device that is supposed to save petrol  ?

If so are they genuine or a con trick ?

Thanks .

[Vauxhall Owners Club]

I think they are 'snake oil' and don't really work.
Maybe best to look at different driving styles, easiest way is to find a spot where your foot is hardly touching the throttle....its difficult but its how I drive nowadays, rather than the foot flat down of my youth