Q: What is the purpose of the Evaporative Emission Control System (EVAP) and Canister on Ford Explorer Sport Trac?
A: The fuel vapors from the throttle body, intake manifold and fuel tank are captured and stored on the EVAP. These vapors are then conveyed by a charcoal canister into the combustion chamber while engine is in progress. So far, it has gone from a system with an activated carbon canister to one that is electronically controlled including other parts of its composition. The inspections vary with the presence of loose or damaged components, smell of gasoline, or leakage of fuel. An increase in fuel pressure is checked by either removing the gas cap or using a SCAN tool. In case where there is increased pressure, tests are conducted on hoses, evaporative emission valve, and charcoal canister. Also, inspections include smelling for fuel vapor in the engine compartment as well as checking hoses and VMV voltage.