What to know about the Evaporation Vent Solenoid:
Your vehicle is furnished with an evaporative emissions control system that effectively regulates fuel vapors created in the fuel tank. It processes them via an emissions control canister, or charcoal canister, and then vents the vapors to the engine to be burned with the air/fuel mixture. In the evaporative emissions system, a series of valves controls the flow and permits for diagnostic testing by the engine control module. The vent solenoid, or vent valve, performs the work of introducing clean air into the evaporative emissions system to carry the fuel vapor to the engine. The vent valve closes when the engine control module commands it to for the purpose of leak tests. When the vent valve is closed, the evaporative emissions system is pressurized and tested for leaks. If it is sealed and no pressure is lost, the test passes. If the pressure drops, the engine control module assumes a leak is present and turns on the Check Engine light.
One of the most common failures in the emissions system is the vent solenoid. It can stick open, making the engine control module to think a leak is present, or it can stick closed. A closed vent valve can make refueling difficult as the pressure in the fuel tank isn’t vented. The fuel nozzle will click off regularly, making it tedious and frustrating to fill your fuel tank.
Facts to Note:
An evaporation vent solenoid code could be linked to a loose fuel cap.
How to Fix:
The evaporative vent solenoid is checked to confirm that it needs changing
The faulty solenoid is removed
The new solenoid is installed
The engine is scanned for codes
The vehicle is road tested for correct operation and that no Check Engine light comes on
The vent solenoid is prone to failure from dust and dirt in the environment such as gravel roads, and will need replacement sooner than if operated only on pavement. If the fuel tank is difficult to fill or the Check Engine light has been diagnosed as a vent solenoid failure, you will need one of your expert technicians to change the evaporation vent solenoid.
Common symptoms indicating you may need to change the Evaporation Vent Solenoid:
Check Engine light is on
The fuel tank may be hard to fill as the fuel nozzle can click off prematurely
Importance of this service:
The vent valve is an essential diagnostic solenoid for the evaporative emissions system, however the linked signs are more of a nuisance than a safety or operating problem.