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Q: Check engine light is on. The gas cap is okay and the vent sensor by crankcase seems okay too. What could it be?

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Dignotic test showed air flow, checked gas cap, some sensor of or by crankcase. Any thing you could help with?

My car has 102376 miles.
My car has an automatic transmission.

The issue could be the evaporative emission vent purge valve on the vapor charcoal canister. I recommend using a sniffer that is used for butane and check for a fuel leak around the vent purge valve and see if there is a gross leak. If so, then I recommend replacing the vent purge valve on the vapor charcoal canister. If you need further assistance with your check engine light being on, then seek out a professional, such as one from Your Mechanic, to help you.

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