Why is your astra 1.8 16v convertible unable to drive past a petrol station very poor mpg how do you get more?
These engines are not reckoned to be "thirsty".Suggest you get
it checked out to see if it is wasting fuel through perhaps a
faulty injector or choked air filter.Maybe a dragging brake?A
session on a vauxhall dealer's diagnostic computer could be
advantageous.If no fault can be found,it will probably be a right