For years, everytime I added gas, I heard a hiss sound when gas cap was loosened. Now I do not hear that hiss. Was the hiss sound normal due to normal pressurizing the fuel tank and part of the SMOG system? Does not hearing the hiss mean I will have troubles passing the next SMOG check? Just had two fuel lines from gas tank to filler replaced. Did find cracked leaking rubber fuel lines.
Thanks for help. Dave_s