Most cars now have a MPG readout display, but for those of use who don't have one or want to check to see if the readout is correct. This is how to check your cars MPG.
Go to the gas station and fill up your car as you normally do. First thing after you fill up is record your mileage or you can set your trip meter if you have one.
Drive how you normally do. When your car is near empty, go to the gas station. Try to get it as close to empty as you can for the most accurate reading. Now fill your gas tank again as you normally do. Record how much gas was filled into the tank this time. Replacing the gas used to drive is an excellent way of calculation gas used.
Ok now we have the mileage driven and the amount of gas that it took to drive those mileage. Divide the mileage by the gallons of gas used. This will give you a very accurate MPG for your car. MPG can fluctuate a lot depending on driving conditions.
