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Q: Gas tank lets small amounts of gas

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I've got a problem with the gas tank. When it is empty and I go to fill it up, it can only let in small amounts. It looks as if it is full. Why is this happening?

A: Hello. This commonly occurs on this vehicle...

Hello. This commonly occurs on this vehicle. The problem is typically with the evaporative emissions system vent valve. The vent valve is supposed to open when filling your tank to allow fuel vapor to exit the tank and keep the pump from shutting off.

This valve may have failed or there may be a restriction in one of the lines. I typically test this by doing a smoke test on the system which opens and closes the valves with a scan tool. This allows me to determine of the valve is bad of if there is a blockage. If you plan on having this repaired, consider YourMechanic, as a certified mechanic can come to your home or office to diagnose and repair this.

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