I have a 2000 GT and the MPG fluctuates badly, Just filled it up the other day and maybe driven it maybe 20 miles city and already an 1/8 of a tank is gone. Getting like 8 to 10 miles to gallon from what it says; it has never been very accurate. On the highway when I open it up to say 70 MPH, the MPG stabilizes to around 25 MPG and maybe 340 to the highway on a tank. I have a cold air intake in it also. I also smell oil and gas while sitting at a light or when I back the car in to garage. The car runs very good and smooth it seems, no hiccups or sputtering.