When the check engine light in your car comes on, it could be for a number of different reasons. One of these reasons occurs when your car's oxygen (O2) sensor stops working. This sensor is an important part of your vehicle; and fortunately, it is relatively inexpensive to replace. Here are three things to know about O2 sensors.

What Are They?

An O2 sensor is a small component in your car, but it serves an important role. This sensor is typically located near the catalytic converter inside your engine compartment.

The O2 sensor is responsible for monitoring the amount of oxygen in the exhaust your car produces when running. The purpose of the sensor is to keep the ratio of oxygen stable. If the exhaust does not get enough oxygen in it, it becomes too rich. If it gets too much, it makes the ratio lean. As this happens, the sensor tells your car how much gas to use.

What Happens When The Sensor Fails?

If your O2 sensor is not working properly, it can have several effects:

• Your car will be placing too much pollution in the air
• Your car will use more gas than necessary
• It could cause failure of your catalytic converter

When a sensor is bad, you may notice symptoms, or you may not. Some symptoms you may experience are poor idling or trouble starting your vehicle. You may also discover that you are filling up your gas tank more often.

In addition, your car may not pass an emissions test, if this is required in your county.

How Is This Problem Diagnosed?

To diagnose this problem, an auto repair shop will probably begin by running a diagnostics test on your vehicle. This will detect the reason for the engine light coming on. If you need this part replaced, you can expect to pay $201 to $316 to have an auto repair shop replace it for you.

This is a small amount to get your car running well again, especially considering the additional expenses you could incur if you do not replace it. If your catalytic converter stops working because of this, you can expect to pay up to $874, not to mention all the extra money you will spend on fuel.

Check engine lights can signify many different problems, but a common one is a faulty O2 sensor. If you would like to find out what is causing your car's check engine light to be on, contact an auto repair shop like Car And Truck Services Inc. in your area.