: The Enlightenment during the 17th â 18th century produced philosophers and scientists who focused on human reason and rational thought to solve problems and provide ethnical systems for living. Enlightenment thinkers believed in natural over supernatural forces or laws.
A purge valve is the part of the vehicle Evaporative Emission Control (EVAP). system. The EVAP system prevents fuel vapors in the fuel tank from escaping into the atmosphere.
The ECM commands the EVAP Purge Solenoid OFF once the system has reached a predetermined level of vacuum. This test verifies if a vacuum can be achieved in the EVAP system. Failure to develop a vacuum may be caused by a large leak or a restriction.