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Check Engine Light: What Might Cause It, How To Fix It

When you’re looking for the best auto repair mechanic in American Fork, Main Street Mechanic is constantly striving to provide world class service better than the rest! Our reputable team provides dozens of years of experience, ASE Certification and ongoing education, and a commitment to excellence. Whether you’re looking to get an oil change in American Fork, inspect the engine, or replace your vehicle’s brakes, Main Street Mechanic is the best choice in American Fork for all your vehicle repair and maintenance needs.

Since 2005, Main Street Mechanic has helped thousands of local American Fork and Utah County residents with world class auto mechanic services. When your check engine light comes on, it’s important to get your vehicle inspected as soon as possible to prevent any problems from growing worse and more expensive.

Main Street Mechanic is proud to have invested hundreds of thousands of dollars in world class diagnostic equipment so we can identify the issue quickly, effectively, and efficiently. As we always like to say – the cheapest mechanic is the one who fixes the problem the first time. That’s why we’ve invested so much of our own money into the highest quality diagnostic equipment and the most highly trained technicians. We believe this is just one of the many reasons we’ve been honored to have been voted Best Auto Mechanic of Utah Valley 3 years in a row!

In this article, we’ll go over some issues the check engine light might signify and why it’s crucial to fix the issue as soon as possible.

Engine – Mass Airflow Sensor or Intake Tract

The engine’s MAF (mass airflow sensor) is responsible for measuring the amount of air entering the engine, helping to determine what amount of fuel is necessary to run your engine properly. Any leaks before or after the MAF sensor in the intake tract can trigger the check engine light. Sometimes, the sensor simply needs to be cleaned to fix the issue. Other times, the sensor may be due for a replacement. If left untreated, a broken MAF sensor can cause failure of other engine parts and reduce performance/fuel economy.

Gas Cap

Believe it or not, your gas part is an important part of an entire, sealed system responsible for recirculating gasoline vapors from your gas tank, keeping them from escaping into the air. A faulty gas cap is one of the more common reasons behind a check engine light coming on. If you have left your gas cap open or if the gas cap is no longer closing the way it’s supposed to, you will likely see your check engine light come on very quickly. If not fixed, a faulty gas cap can cause fuel loss and errors in your recirculation system.

Catalytic Converter

The catalytic converter in your vehicle split unsafe gases from safe ones. It helps to reduce the amount of harmful carbon monoxide that is released into the environment. A catalytic converter does not typically fail on its own – it’s usually caused by something else that is failing in the system. Because of this, simply replacing the converter or the oxygen sensors around it will not fix the problem. A blown head gasket, for example, is a common cause behind a failed converter. If left unchecked, your vehicle will not be able to pass emissions, will experience reduced performance, and the issues throughout your entire system will continue to get worse until the root cause is identified and taken care of.

Faulty Oxygen O2 Sensors

The oxygen sensors in your vehicle help the measure the amount of unburned oxygen in your vehicle’s exhaust system. If faulty, your engine will burn more fuel than needed and may cause damage to your spark plugs and catalytic converter. Oxygen sensors function in hundreds of degrees exhaust temperatures and are prone to fail once every 80,000 miles.

Spark Plug Misfires

Spark plugs ignite the air/fuel mixture within the combustion chamber of your vehicle, but if anything is wrong in the timing of that spark, you’ll have a misfire. There are a number of issues that can cause a misfire, including:

-        Defective ignition coil

-        Defective fuel injector

-        Vacuum leak

-        Worn spark plugs and/or wires

-        Bad compression

If not fixed properly, your vehicle will experience reduced power, reduced fuel economy, and eventually mechanical failure in the engine.


If your check engine light comes up, make sure to call Main Street Mechanic right away! We carry out each step with attention to detail and an exceptional level of care. We vet which parts are used, who we employ, what systems we utilize, and how to best complete the task at hand. Everything is done with cost-efficiency in mind to get you the best service and the greatest longevity of your vehicle. Main Street Mechanic in American Fork is more than just your average auto repair service. We are a family-owned shop that has become one of the most respected names in the industry and in the community. If you’re searching for a trustworthy auto shop with educated, friendly specialists, choose the mechanic that will strive to earn your business over and over again from the very first moment you enter our shop. We offer a free customer shuttle and an industry-leading 3-year / 36,000 mile warranty on most repairs. If your check engine light comes on or if have any concerns or questions or need to schedule an appointment, call 801-756-2661. 





7:30 AM - 6 PM


337 West Main Street
American Fork, UT 84003


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