I don't get the standard hiss when unscrewing the fuel filler cap, and am throwing the 0111 EVAP control system flow code. Questions:

A. Will a clogged EVAP valve cause a lack of vacuum formation in the gas tank?

B. Or is that strictly the effect of a bad gas cap which no longer holds a proper seal?

C. How puch of a PITA is it to clean the EVAP valve with wd-40? Do the hoses come off fairly easily, or are they a monster pain like the fuel filter? Just want to make sure I give myself enough time to clean the thing.

 

I don't think you can read too much into getting a hiss when removing the gas cap My normally functioning system seems to hiss sometimes and not others.

Depending on where you live you may be dealing with a lot of rust when trying to access the valve.