The Check Engine light or Service Engine Soon light is one of the most misunderstood lights on an automobile’s dash. There are any number of reasons why this light comes on ranging from a loose or cracked gas cap to problems with the catalytic converter. Regardless of what some websites will advise you, it’s not always as easy as going to your local parts store to have them check the error code from your vehicle’s computer system. In this post, I’ll give you some basic information on the Check Engine light and Service Engine Soon light. I’ll also outline some of the common causes for this light to come on and why you shouldn’t ignore it when it does.

What is the illuminated Check Engine Light or Service Engine Light telling you?

Your automobile is controlled by a very sophisticated computer system designed to keep your vehicle running its best while also protecting the environment from excess emissions. Part of the vehicle’s computer includes an onboard diagnostic (OBD) system that is constantly checking the electronic sensors and emission control systems. When the OBD detects a possible problem, it activates the Check Engine light or Service Engine Soon light on your dashboard. The nice thing about the OBD system is that it often detects a little problem that you can take care of before it becomes a major repair issue.

Why you shouldn’t ignore the Check Engine Light

The entire purpose of the Check Engine light or Service Engine Soon light is to alert you to a problem with your emissions control system. While you don’t have to immediately stop your vehicle and have it towed to our shop when this light comes on, it is best to schedule an appointment as soon as possible to have it fixed. By ignoring the light and delaying the repair, you could cause considerable damage to components like the catalytic converter. That’s a costly part to replace and something that should be avoided, if at all possible.

Why does the Service Engine Soon light come on and what should you do?

One of the most common reasons the light comes on is from a vacuum leak caused by a loose or faulty gas cap. Yes, this really can cause the Check Engine light or Service Engine Soon light to illuminate. Don’t worry, though. If this is causing the problem, it’s simple and relatively inexpensive to fix. You can even do this yourself. Start by removing the gas cap and putting it back on, making sure it’s installed correctly. Next, you’ll need to drive the vehicle several times to allow the Onboard Diagnostic (OBD) system to reset. If this was the cause of the light being on, it will turn off. If this doesn’t correct the problem, the next step is to replace the gas cap. Don’t be tempted to buy a cheap one. Instead, purchase a gas cap that’s expressly made for your vehicle. Once you replace the gas cap, you’ll have to drive it again a few times to see if the light will turn off.

If you follow these steps and the Check Engine/Service Engine Soon light remains on, schedule an appointment with Country Road Auto in Lincoln Park, NJ. Diagnosing why a Check Engine or Service Engine Light comes on isn’t as simple as getting a reading of the ODB codes at your local auto parts store. There are hundreds of codes that could indicate a problem with any number of components. Our ASE-Certified Technicians have the training and experience to get the source of the problem and correct it. We even have a coupon so you can save $25 on diagnostics associated with a Check Engine or Service Engine Soon light. Click here to get that coupon now.

Here are some additional reasons a Check Engine or Service Engine Soon light comes on

A Faulty Oxygen Sensor: For your car’s engine to function efficiently, it requires a particular ratio of oxygen to fuel. When there’s not enough oxygen, your engine will be running “rich” because there is fuel left over from the combustion process. Too much oxygen will cause poor engine performance and may even damage the engine. The oxygen sensor works with the engine’s computer system to gauge and adjust the air/fuel ratio. When the sensor is faulty and not working, the computer cannot adjust the air/fuel ratio causing the light to come on. When the oxygen sensor isn’t working, you’ll notice loss of engine power. If you don’t have the sensor replaced, the spark plugs will become fouled and you could damage the catalytic converter.

Spark Plugs & Wires: Worn out spark plugs and wires will hinder the combustion process. The spark plugs are designed to ignite the air/fuel mixture during engine combustion. If the plugs are misfiring, you’ll begin to notice some hesitation or jolting when you accelerate. Don’t wait until the spark plugs and wires are completely worn out. It’s best to have them replaced at the mileage recommended in your owner’s manual.

The Mass Airflow Sensor is Faulty: This sensor is responsible for measuring the amount of air passing through the air filter and then communicating that information to the computer so it can send the right amount of fuel to the engine. When the mass airflow sensor has gone bad, you’ll notice a decrease in gas mileage. If you ignore this, your vehicle may then begin to stall. Eventually, you risk damaging the spark plugs, oxygen sensor, and/or the catalytic converter.

Final Remarks Regarding the Check Engine and Service Engine Soon Light

When your Check Engine or Service Engine Soon light comes on, get it taken care of as soon as you can. By doing so, you’ll avoid any further damage to your engine and exhaust systems. A catalytic converter is a very expensive part to replace. That’s because it is made from rare metals – platinum, palladium and/or rhodium. No one wants a high repair bill. Taking care of minor issues when your vehicle first alerts you to a problem is the prudent course of action. If your Check Engine or Service Engine Soon light is on, click here to schedule an appointment with Country Road Auto in Lincoln Park, New Jersey.