question about car

Hi I took My car to pep boys today the problem was that the PCV tube and valve needs to be replaced does this have any thing to do what this?:EVAP small leak/no flow conditon:Exlanation the evaporative emission system is monitored for it's ability to hold vacuum problem cause Defective or loose fuel cap EVAP canister or hose cracked-not connected purged or vent soleniod defective vaccum leak at engine

How long will it take before the engine light goes off?

after it is repaired, it will be reset by the tech. if the gas cap was loose and you tightened it, it has to pass its own test 3 times before the light will go out. Roy