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Q: Service Engine Light

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My service engine soon light came on yesterday and i took it to autozone and said that i have an air leak causing me to burn more gas than usual. The gas cap was really loose so i tightened it up and also filled the gas tank. Service light still on. Checked my air filter and there is a small nick in the seal. Is it possible that that could be it?

My car has 90372 miles.
My car has an automatic transmission.

A: The code you may have got indicating an air...

The code you may have got indicating an air leak may have been a code for fuel vapor leaks. The loose gas cap can cause the fuel in the fuel tank to evaporate out of the loose gas cap. The evaporation of the fuel in the tank may cause you to think the engine is burning gas faster than it use too. You are most likely burning the same amount of fuel but evaporating fuel vapors out of the gas cap can evaporate about gallon of fuel for every hour you are running the engine or in high heat weather. It is like a gas can stored with the cap off. The gas would evaporate pretty fast. You should have the check engine light scanned by a mechanic like one from YourMechanic to see if the code is for the vapor leak from the gas cap and just clear the codes to turn off the light for you or there is other problems that need diagnosed. The air filter nick is not a problem. I suspect the gas cap was the problem but the light will not go off without mechanic with a scanner clearing the code for you.

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