Top 3 Most Common Causes of the Check Engine Light
1. Oxygen Sensor : The oxygen sensors in your car helps determine how much fuel you burn. A defective oxygen sensor effects mileage calculation and leads to a decrease in fuel economy.
2. Gas Cap : It might seem silly that something as small as a gas cap can trigger your warning light, but the gas cap keeps fuel from evaporating, keeping your emissions and gas mileage low.
3. Catalytic Converter : A dying catalytic converter leads to lower gas mileage, and makes it difficult for your engine to accelerate. If you notice any of these problems, take your car to your mechanic as soon as possible to fix it.