A car's purge valve is a mechanism that directs the vapors emitted by the engine fuel from the fuel tank to the intake manifold. The purge valve also stores the fuel vapors for future combustion, allowing it to be recycled back into the engine combustion process when needed.
The purge valve also helps in preventing toxic gases from being released into the atmosphere, since it redirects the gases from the fuel instead of emitting them. It also helps the engine use fuel more efficiently, which then contributes to less fuel consumption. The valve also collects air from outside the car and moves it to the fuel tank, helping the engine burn the fuel more effectively by providing it with more oxygen.