Do you know how far you can go before your fuel gauge hits E? Image from Flickr.

Miles per gallon is the big buzzword regarding vehicle performance, but do you really know the MPG of your ride? Sure, the EPA offers estimates of miles per gallon, but your vehicle’s MPG may vary by up to 15 miles per gallon. Knowing miles per gallon can help you be more in touch with your car and alert you to issues that may be developing. So how do you figure your MPG?

Knowing your MPG

Figuring out your miles per gallon starts with something that may be a bit painful – filling your tank. Once you have a full tank of gas in your car, write down the mileage on your odometer. Every time you put fuel in your tank, fill the tank to the top. Write  down the odometer mileage and how many gallons you put in the tank. Once you have filled the tank four or five times, you have a place to start. Divide the total number of miles traveled by how many gallons of fuel you put in the tank. This gives you a miles per gallon number.

How Miles Per Gallon can change

The first thing you will notice once you start tracking MPG is that it can vary greatly. Highway MPG is usually much higher than in-city MPG. You should track your miles per gallon for at least a month to get a good average. Once you know what your car usually gets for MPG, you can start working to improve the efficiency of your vehicle.

Improving your MPG

Once you know the average MPG your car usually gets, you can experiment with ways to improve it. Start with changing the oil in your vehicle. Keeping the oil in your engine fresh — changing it every 3,000 to 5,000 miles — can often improve your MPG by 5 to 7 miles. Changing the air filter can also improve MPG by 10 to 15 percent. Spark plugs that have been used for more than 30,000 miles are also fuel hogs – so change those out. You should also check your tire pressure every time you fuel up your car. Every time you make one of these changes, record the miles per gallon and decide if the change was worth it.