John Linden: Hi! I'm John Linden, Master ASE Certified Technician and North America Training Manager for Midas International Corporation. Today I am talking about how fuel injection and spark plugs affect the fuel efficiency of your vehicle.

Years ago there was a part on a vehicle called a carburetor. Somewhere around 1988 that part was replaced by all automotive manufactures with electronic fuel injectors. This was a major change in the way the fuel was delivered to the engine.

This change made for a more efficient fuel delivery and a dramatic reduction in emissions. With this change from carburetion to electronic fuel injection, maintenance of the fuel injectors is important to help maximize performance and reduce harmful emissions.

With the technology that's built into today's vehicle, the computer compensates for both partially clogged fuel injectors and worn out spark plugs. So even when the engine feels like it is running smoothly, you may be wasting fuel.

The Motorist Assurance Program or MAP recommends that the fuel system be cleaned and serviced once a year or about every 15000 miles. Gasoline and flex fuels do a poor job of keeping the fuel injectors clean. They get a built up of carbon and other deposits and while this happens the fuel injectors have a tendency to leak or drip causing to decrease in fuel mileage.

If they get clogged or restricted they will turn on a check engine light which could lead to a costly repair. There are a number of ways to properly clean fuel injectors; most of them require special equipment and chemicals.

While there are few products that can be purchased over the counter for the do-it-yourselfer, they are not as effective as having it done professionally. A little preventive maintenance can save you time and money. When the spark plug starts to wear out, the computer compensates for this wear by adjusting the timing and the fuel delivery. Unfortunately the average driver does not notice anything other than a slight loss of power or poor gas mileage. If the spark plugs get too worn this will turn on the check engine light and that could lead to a costly repair.

Bottom line; if your spark plugs are worn out you will be using more fuel than you need to. Years ago it was easy to change the spark plugs with a few simple tools and some basic mechanical knowledge. Today that's changed; just locating the spark plugs could be challenge for do-it-yourselfer. Not to mention some vehicles requires special procedures.

If these procedures are not followed it can lead to a very expensive repair. The best thing you can do is to check your factory schedule maintenance to see when the manufacturer suggests changing the spark plugs and take it to your mechanic.

So that's how you can help increase fuel efficiency and spark plugs.