i have just changed my motability car and got a meriva 1.4 100ps petrol. i have since done 140 miles in it but it has cost me 35 (6 gallons of petrol) which equals the car doing 25 mpg. i have used motorway as well as round town. is this unacceptable for this car. it hasnt got a trip computer on it so i cant verify its only getting 25 mpg except that petrol guage is flashing when i refill it. its costing more to run than i thought and i was going by what vauxhall claim it supposed to do. can any one advise what steps i can do ? thanks