Unexpected Reasons Your Check Engine Light Is On

Unexpected Reasons Your Check Engine Light Is On

| By: Christian Brothers Automotive

Editor’s Note: This blog has been updated as of December 2020.

We’ve all been there – you get in your car, ready to leave for work, and the check engine light pops on. Whether your light is red, orange, or yellow, it’s usually accompanied by an onset of panic, anxiety, or frustration.

What Is a Check Engine Light?

The check engine light, also called the malfunction indicator lamp, is a signal from the car’s engine computer that something is wrong with your vehicle. It’s your car’s way of giving you a heads up that something is malfunctioning during operation.

What Does Your Check Engine Light Mean?

Your engine control unit monitors your engine's performance along with other related components that keep your vehicle operating properly within certain emissions standards. When this computer collects data that is outside of normal operation, it records a specific fault code that relates to the issue. The check engine light then illuminates, to let the driver know this has happened.

In most cars, aflashing check engine light means something should be done immediately, as the problem could be dangerous, while a steady light indicates an issue that should be checked soon.

What Does the Check Engine Light Mean?

There are few feelings more intimidating and annoying than watching your car’s check engine light click on. Since the standardization of check engine lights in 1996, it has confused many drivers. This is due to the wide variety of issues the light could be indicating.

Unfortunately, driving around, hoping, and praying the light turns off won’t do you or your vehicle much good. If your check engine light has recently come on, there are two major categories of problems your vehicle may be facing.

Fuel System Issues

Faulty gas cap - Your vehicle is pretty good at warning you of any potential trouble. Something as simple as forgetting to replace the gas cap could cause your “check engine” light to come on. This is because the gas cap keeps vapors from escaping the fuel tank. A loose or broken gas cap can dramatically reduce fuel efficiency and increase emissions.

MAF sensor - Mass airflow sensors are a common item to go bad in vehicles. A MAF sensor sits near the engine and reads how much oxygen is being let into your engine along with gasoline. There is a certain level of oxygen the engine requires to run efficiently and stay safe. When the MAF sensor goes out, your car no longer reads these important levels. This is a simple fix that requires only a quick replacement.

Faulty ignition - Spark plugs ignite the fuel as it flows through the engine’s cylinders. Failing to replace a spark plug could lead to catalytic converter failure or other serious problems.

Exhaust Problems

Catalytic converter – The catalytic converter takes dangerous gases your vehicle produces and makes them less harmful. If your catalytic converter fails, you are putting yourself and the environment in danger of high output of carbon monoxide and other harmful gases.

O2 sensor - The combustion process requires a very delicate mixture of chemical gasses. The O2 sensor monitors these gases to make sure the right amount of oxygen is present. When the O2 sensor fails, the vehicle cannot perform as needed. This significantly reduces fuel economy and could end up costing thousands in damages. Replacing your O2 sensor at the first sign of trouble will save time and money in preventable repairs.

Check Engine Light Service & Repairs

Next time your engine light comes on, bring it directly to Christian Brothers Automotive. Not only do we have the proper tools to diagnose the issue, but we also have the experience and knowledge to deliver you a durable repair that gets you on the road again.

Following a diagnostic procedure or test, our experts will provide an itemized estimate for you to look over and approve. We’ll never make any service decisions without first asking for your approval.

Whether your check engine light recently came on, or you’ve been looking at it anxiously for hundreds of miles, we can help you determine the problem and fix it with reliable and professional services. Call Christian Brothers Automotive today to schedule your next service appointment today! Explore our site to discover why we are continually chosen to meet our guests’ auto care needs.

Find your closest CBA auto mechanic shop by using our store locator here.

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