Common Causes of Check Engine Light Illumination

If your check engine light is on or flashing, it’s time to visit Milito’s Auto Repair in Chicago, IL. 

An illuminated check engine or service engine soon light indicates that a part of your vehicle’s system is not operating properly, and seeing this light on your dashboard can be alarming. This small yet significant warning light can indicate a range of issues, from minor glitches to serious problems that require immediate attention. Understanding what triggers the check engine light can help you take appropriate action and avoid potential damage to your vehicle. Here’s an overview of the most common causes and how Milito’s can diagnose and fix these issues to keep your car running smoothly.

Common Causes:

  • Oxygen Sensor Issues: A faulty oxygen sensor can affect engine performance and fuel efficiency. It’s crucial to replace a malfunctioning sensor to maintain optimal engine function.
  • Catalytic Convertor Problems: A catalytic converter is the component of an exhaust system that converts harmful pollutants into less harmful emissions. Driving with a faulty converter can result in an increase in these harmful emissions and a loss of power, especially during initial acceleration. Our technicians diagnose any troubles that could lead to the replacement of your catalytic converter. If a replacement is necessary, they work with you to make the process as easy as possible.
  • Loose or Faulty Gas Cap: A loose, damaged, or missing gas cap can trigger the check engine light. This is an easy fix but should be addressed promptly to avoid fuel vapor loss.
  • Mass Airflow Sensor (MAF Sensor) Fault: The mass airflow sensor monitors the amount of air entering the engine. Based on these real-time inputs, the engine control unit estimates the amount of fuel mass needed to keep air and fuel in balance. A faulty sensor can cause poor fuel economy and performance issues.

  • Spark Plug and Ignition Coil Issues: Worn-out spark plugs or faulty ignition coils can cause misfires and trigger the check engine light. In today’s cars, if a spark plug fails and can no longer ignite the air-fuel mixture, then the most obvious event should be the check engine light coming on or even flashing. Regular replacement is essential for smooth engine operation.
  • EGR Valve Malfunction: The EGR valve helps reduce emissions and improve fuel efficiency. Symptoms of a bad EGR valve include poor engine performance, increased fuel consumption, pinging or knocking sounds and more.
  • Vacuum Leaks: Leaks in the vacuum system can cause a variety of issues, including a rough idle and poor fuel efficiency. Identifying and fixing these leaks is important for engine health.

Advanced Diagnostics with Milito’s

The check engine light can signal a range of issues, from minor to serious. At Milito’s, our expert technicians use advanced diagnostic tools to identify and fix the root cause of the problem, ensuring your vehicle runs smoothly and efficiently. If your check engine light comes on, it’s time to visit Milito’s Auto Repair. Schedule your appointment today.

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