San Mateo auto repair

Why Is My Check Engine Light On?

Every vehicle has a long list of warning lights that sometimes makes an appearance. But the one that most car owners dread the most is the check engine light. This yellow light is a signal that something is wrong, most of the time, engine-related. So what do you do when it comes on? And what does it mean? Today, we will be answering those questions.


Not all check engine lights mean the same thing; some circumstances are more urgent than others, so please pay attention.

  • If your light only lights up in specific scenarios and turns off, you should pay close attention to how your vehicle performs when it is on.
  • If the light stays on, without any noticeable performance problems, you should still take your car to a mechanic. He or she will be able to decode the computer to see if there's a problem that needs to be fixed. 
  • If the light stays on and you DO experience vehicle performance issues, you should take it to a mechanic.
  • If the light is on and blinking, please pull over to a safe location and call for a tow. When this happens, it is deemed unsafe to continue driving.

What Can the Check Engine Light Indicate?

  • Loose Gas Cap (This is the easiest fix that often requires tightening or replacing the gas cap.)
  • Broken Oxygen Sensor 
  • Old Ignition Coils and Spark Plugs
  • Faulty Catalytic Converter
  • Faulty Mass Airflow Sensor

NEVER Ignore the Warning!

It's easy to overlook a check engine light and pray that it turns off on its own, but that could lead to more expensive and extensive problems later on. To be on the safe side, you should bring your vehicle to Four Car Garage as soon as you can. You can trust our skillful team to provide you with the 5-star quality auto repair service and maintenance you deserve. You can give us a call at (650) 235-4696 or visit our repair shop in San Mateo, CA for any questions or concerns.

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