Check Engine Light – What Does it Mean?

There it is, glaring at you from the dashboard, the dreaded check engine light. Even though it doesn’t tell you why you should check you engine, it usually causes panic. Do you immediately pull to the side of the road and call for a tow truck? Or drive directly to your mechanic?

Take a deep breath. While the most common reasons for the check engine light to illuminate your dashboard require your attention, they aren’t necessarily an emergency. Or at least they won’t become one if you take care of them. As long as you’re not on a long distance or cross country trip, you can continue to your destination.

Once you’ve arrived, the first thing you should do is check your gas cap.  A loose, damaged or missing gas cap will trigger your engine light. Obviously, if it’s not there, that’s the problem. If it is there, check for damage and make sure it is secure.

Fuel vapors can leak out if the cap is loose or damaged. This will reduce your gas mileage and increases emissions. If the light is still on after you’ve made sure the gas cap is in good shape and on tight, then the gas cap isn’t your problem.

These are some of the common reasons for the check engine light to come on. If you are handy when it comes to automotive repair, you may be able to diagnose or even fix some yourself. If not, it’s probably time to give the mechanic a call and set up an appointment. They will hook your vehicle up to an OBD-II or on board diagnostics scanner to find out what the problem is.

Check Engine Light - What Does it Mean?

Mass Airflow Sensor

This sensor, also known as an MAF sensor, calculates the amount of air coming into the engine so that the computer can add the right amount of fuel. A bad or faulty MAF sensor can cause the engine light to come on.

An air filter that’s dirty and overdue to be changed can be the cause of this issue. It can cause your vehicle to have reduced gas mileage, increased emissions or to stall. Changing your air filter regularly can help prevent this.

Oxygen Sensor

The average vehicle has two to four oxygen sensors. These sensors analyze the amount of oxygen in a vehicle’s exhaust to determine how much fuel has been burned. A faulty sensor will provide inaccurate information to your vehicle’s computer, significantly reducing gas mileage and increasing emissions.

If one or more of the oxygen sensors is bad, the code received by the OBD-II scanner will tell you or your mechanic which sensors they are. Addressed  immediately, this is not a serious problem. If ignored, it could affect your catalytic converter. Not only more serious problem, an issue with the catalytic converter can be expensive as well.

Spark Plugs or Wires

If you experience slight jolts during acceleration along with the check engine light, the culprit could be the spark plugs or wires. Spark plugs seal the combustion chamber and provide a gap for a spark to jump across. This initiates combustion in your engine. Spark plugs that are failing will misfire. It’s this misfire that causes the jolt you feel when you press down on the gas pedal.

Spark plugs in newer cars should last up to 100,000 miles, but they do wear out and replacing them is part of normal maintenance. Old worn out spark plug wires can also contribute to this problem. They should be replaced along with the spark plugs or if they show obvious wear or damage. Neglecting this issue will not only impair your vehicle’s acceleration, it can also cause damage to your catalytic converter.

Catalytic Converter

To reduce noxious exhaust gasses, the catalytic converter’s job is to convert carbon monoxide and other harmful materials into harmless compounds. Regular vehicle maintenance can prevent the failure of the converter. Typically, other components of your vehicle which are old or faulty are the cause of the catalytic converters demise.

As it fails, the catalytic converter will no longer convert carbon monoxide into less harmful emissions. If it fails completely, your vehicle will eventually stop running. Replacing the catalytic converter will be a significant blow to your budget. Unless you’re an experienced mechanic, replacing it is not a DIY project.

Check Engine Light - What Does it Mean?

Check Engine Light Still a Mystery?

You’re not alone. Most people are confused by the check engine light and what it could mean. With all the technology in today’s vehicles, it’s best to leave the diagnostics and repairs to the professionals.

Holiday Service Center has been Toms River’s trusted auto service and repair shop for over 30 years. The next time your check engine light comes on, don’t panic. Give us a call or stop in and let us worry about it. Our ASE-certified technicians will provide the best service possible and have you back on the road in no time.


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