What Does It Mean When the Check Engine Light Comes On?

What Does the Check Engine Light Mean? in San Diego, CA

When the check engine light comes on, something needs your attention right away. The issue may be serious and expensive, or it may be a minor issue like a loose gas cap. The Chula Vista cheap auto insurance providers at American Tri-Star share a few things you should know about your check engine light and what to do when it comes on.

Is the Light Blinking or Steady?

The check engine light will either light up and remain constant or it will blink, depending on the severity of the issue. When the light stays steady, it means the issue isn’t an emergency. Still, it’s important to look into the cause right away. A blinking light usually means a serious engine misfire. If you continue driving with a blinking light, you may end up damaging expensive parts like the catalytic converter. Note that some cars don’t use a blinking light. Instead, the light changes from yellow/orange to red when the issue is serious.

Check the Trouble Code

When your check engine light comes on, your vehicle’s computer will store a trouble code indicating the source of the issue. Trouble codes can be read with a diagnostic computer at a repair shop or with an inexpensive electronic tool you can buy yourself. Since 1996, automakers use a standardized OBD-II system with a list of diagnostic trouble codes to make diagnostics easier. Your car will have a universal connector to attach the diagnostic tool. This connector is probably under your steering column. If you have OnStar with an active subscription, you can even call an advisor to remotely read the trouble code.

Common Causes of the Check Engine Light

While any number of issues can make your check engine light come on, these are the most common:

  • Faulty gas cap – A loose or bad gas cap allows vapors to escape and trigger the error.
  • Mass airflow sensor – This sensor tells the computer to add the right amount of fuel based on air coming from the engine. These sensors usually fail due to improper installation of the air filter.
  • Spark plugs – Your spark plugs seal your combustion chamber and give the spark a way to jump across a space and initiate combustion. When spark plugs begin to fail and misfire, your check engine light will come on. Replace spark plugs around 100,000 miles.
  • O2 sensors – These sensors check how much unburned oxygen remains in your exhaust as it exits the engine. Most cars today have four oxygen sensors.

Worst Case Scenario: The Catalytic Converter

The most serious reason for your check engine light to turn on is if your catalytic converter is overheating or failing. This component works to lower exhaust gases by converting carbon monoxide into a harmless compound. When the catalytic converter begins to fail, your car might not go faster when you press the gas, or you might experience a dramatic drop in gas mileage. Replacing it could cost $2,000 or more.

American Tri-Star is a leading provider of auto, motorcycle, and RV insurance. Chula Vista residents can call 619-827-0522 to speak with one of our friendly representatives and receive a free quote. We hope to hear from you soon.