The car holds 11.9 gallons of gasoline. It uses roughly a quarter tank (3 gallons) to travel 45 miles at the most. WHy is it using so much gas? The car runs fine with no problem, but I know that 1 valve is bent on cylinder 1. I mean, its a honda, even though the valve is bent, could it effect the gas mileage that much? It also has a hole on the bottom of the muffler, probably a 6 by 6 inch hole that probabluy just starting rusting out or something, but could these two factors effect the gas mileage that badly? i mean, this car should give 30 miles a gallon on the highway from the specs. And I am not driving like a maniac, i have been driving 55 -60 mph...no more than that. And I use it mostly on the highway for about a 35 minutes constantly at 55-60mph....what could be the problem?