Does a "check engine" light on mean that you're losing fuel mileage?
This single light has hundreds of reasons to glow. So, it's time to learn about the performance symptoms, like surging, hesitation, chugging, and low power it creates. There are plenty of common issues that activate the check engine light.
Is Your Car's Check Engine Light Constantly On?
The yellow check engine light commonly warns that the engine releases more emissions than expected, often due to a catalytic converter failure. This causes engine misfires, poor fuel mileage, low power, and more. But there are alternative common causes for this issue.
The most common causes for the Check Engine light are:
- Engine misfire: When an engine misfires, it fails to ignite the air-fuel mixture properly, leading to a loss of power and rough running. The onboard diagnostics system detects this issue and triggers the check engine light.
- Evaporative emission leak: An evaporative emission (EVAP) leak can cause the check engine light to illuminate because it disrupts the vehicle's emissions control system. A leak in the EVAP system, allows fuel vapor to escape, leading to increased emissions.
- Loose gas cap: If the gas cap is not properly tightened or is missing, it can allow fuel vapors to leak out, triggering the check engine light.
- Faulty airflow sensor: The airflow sensor measures the amount of air entering the engine to help the system adjust the fuel injection for a perfect air-fuel mixture. If the sensor fails, it'll cause a bad mixture and trigger the check engine light.
- Faulty catalyst: The catalytic converter converts harmful gases into less harmful emissions. If the catalyst is faulty, it increases emissions and triggers the check engine light.
- Lean codes: Lean codes can cause the check engine light to illuminate because they indicate a problem with the air-fuel mixture in the engine. A lean condition occurs when there is too much air and not enough fuel in the air-fuel mixture, leading to incomplete combustion.
- Faulty variable valve timing (VVT): The VVT system controls the timing of the opening and closing of the engine's valves. If the VVT system is faulty, it may not operate correctly, leading to issues such as rough idle, reduced power, and increased emissions, triggering the check engine light.
Stay alert if the check engine lights up on your car's dashboard. Your vehicle might be under progressive damage and can end up requiring hefty repairs in the future; it'll also show considerable fuel loss. So please, keep track of your car's odd behaviors and browse through our articles to find out the information you'll need to share with your go-to auto shop.
