Why is the Check Engine Light on?


The Check engine light is one of those small things in life people often dread. This is unfortunate because it exists to ensure that your car doesn't suffer any excessive damage. It will turn on at the first sign of trouble, so it is important to get to the repair shop for diagnostics as soon as it illuminates. Many times the issue will be small, but the longer you wait the worse the issue will get, as demonstrated by this first check engine light problem.

Catalytic Converter

Perhaps the worst discovery that can be made if your check engine light is on is a faulty catalytic converter. This is the part of the exhaust that turns harsh exhaust fumes into less hazardous emissions and as long as you follow routine maintenance it shouldn't ever need repair, which can be quite costly. However, in order for it to fail there was likely some other trouble that would have triggered the light to come, meaning you waited to long for service!

Failed Oxygen Sensor

A failed oxygen sensor is one thing that can be detrimental to your catalytic converter. However, this sensor is quick and easy to replace or clean in most cases. This part monitors oxygen in the exhaust in order to help ensure the proper air and fuel mixture in the engine. If it isn't fixed you'll see a decrease in fuel efficiency and an increase in emissions.

Faulty Mass Airflow Sensor

This sensor tells your vehicle how much gas to add to the air/fuel mix based on incoming air. If this part becomes damaged or otherwise malfunctions you will also notice a sharp decrease in your miles per gallon. Be sure to replace your air filter as scheduled to help ensure this part doesn't fail.

Misfiring Spark Plugs

The spark plugs are what ignite the air/fuel mixture and should they misfire or be unable to properly perform their function the check engine light will come on. This is a fast and easy fix for most cars and trucks.

Broken or Loose Gas Cap

The best case scenario if your check engine light has come on is if you forgot to tighten the gas cap after filling up. A loose or broken gas cap will allow for fuel vapors to escape through the filler hose, resulting in the check engine light coming on thanks to detection of the fumes by the EVAP system.

As soon as the check engine light comes on be sure to get to your local auto repair shop for diagnostics. If you need check engine light repair in Mountain View be sure to visit A-1 Auto Tech. Our team of talented auto repair technicians will quickly diagnose the issue your car is having and have you on your way in no time. Give us a call at (650) 903-7305 to schedule an appointment for quality auto repair in Mountain View today.

A-1 Auto Tech Inc Blog

Written By Brian Corey

Published By MORBiZ

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