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Q: No preasure release when removing gas cap.

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When filling up for gas there is no preasure release when removing gas cap?

My car has 169500 miles.
My car has an automatic transmission.

Hello, Your car has a system that works to remove fumes and pressure from the fuel tank that is called the evaporative emissions system. The EVAP system prevents fuel vapors from the fuel tank from escaping into the atmosphere. The EVAP system collects and temporarily stores the fuel vapors in the charcoal canister. The charcoal canister is filled with activated carbon pellets that can absorb the fuel vapors. When the engine is running, the fuel vapors are purged from the canister and burned in the engine. The vent control valve (solenoid) controls the flow of outside air in and out of the charcoal canister. When this is not working properly, you may experience the gas pump shutting off prematurely causing it to take a very long time to fill up your fuel tank. This is due to the excess fuel vapor that is present when the purge solenoid is not working properly by releasing these vapors. The gas pumps at the fuel station have automatic sensors on them (for safety reasons) that shut off automatically when too much fuel vapor is present. I would recommend having an expert from Your Mechanic come to your home to take a look at your car to diagnose your EVAP purge solenoid.

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