What Happened to My Fuel Economy?


You notice that suddenly your vehicle seems to be getting worse gas mileage than it did awhile back. Why? What happened?Gas Milage

Like with most things on your vehicle, there can be numerous problems at the root of poor fuel economy. Let’s start with the simple ones and work our way to the more complicated issues:

Tires: This one’s easy. Underinflated tires mean more rolling resistance (think about riding a bike with a low tire), and more rolling resistance means poorer fuel economy. Check your tire inflation at least once a month, while the tires are cold, using a good quality tire gauge. Even a pound or two of underinflation can be enough to cause problems!

Air filter: The air filter is made of pleated paper or fabric elements which prevent pollen, dust and particulates from entering the fuel system where they could do some real damage and cause wear. A clogged air filter can literally smother the engine by restricting air flow. Take out the air filter and hold it up to a bright light – if no light can pass through it, it’s time for a change.

Check Engine light: Your engine relies on a series of sensors which send information to the drivetrain computer to monitor fuel delivery, ignition timing, transmission shift points, emission controls and other functions. If a sensor is sending readings which are outside of normal operating limits, a trouble code will be registered in the engine’s drivetrain computer and the Check Engine light on the dashboard will be illuminated. A technician can then use a code reader or scanner device, connected to the diagnostic connector, to read the codes and determine the cause of the problem.

Oxygen sensor: Engines use an O2 sensor in the exhaust stream to monitor the content of the exhaust gases. Usually, the O2 sensor(s) will last the life of the vehicle, but if an O2 sensor fails it can lead to a rich-running condition and cause the engine to put excessive amounts of fuel into the system.

Questions? Concerns? Call us and we’ll get you straightened out again!