How to troubleshoot p0442 small leak detected

[MissSaturn210]

Hello. I have a 2005 Saturn Ion 2. I have lived with this p0442 code since June, long enough. Code was first scanned at autozone, I was told replace purge solenoid and vent valve solenoid. (done) Check engine light comes back. I took it to the dealership in July. They replaced my fuel tank pressure sensor. The light came back. Dealership didn't offer any suggestions or shine a light on anything else EVAP related. What else should I be looking at? Oh, I forgot to mention I have replafced my gas cap twice and the dealership replaced it a 3rd time. Prior to changing gas cap, I hadn't received check gas cap message until last week. It comes and goes, and not necessarily after fueling up. Thank you for having me! Suggestions highly appreciated!

[fdryer]

Here's some background info from a past thread; https://www.saturnfans.com/forums/sh...d.php?t=211396

[rjc862003]

have it smoke tested I am 99.99999999% sure its the lines
the fuel and vapor lines on these are notorious for rotting out
you can pickup a generic Nylon kit and replace it all with nice rust proof nylon for less then a 100 bucks
https://www.ebay.com/itm/274869251493

you can do this in the driveway its plug and play just run it next to the existing line and zip tie it up so its neat and out of the way (keep it away from the header and exhaust)

the E-Clips on the quick disconnects can be pain to get off

[bern]

The filler pipe was often the last repair (back in the Saturn dealer). The filler pipe has a plastic smooth donut seat attach to the top end of the filler pipe. The donut seat will lose the air tight seal to the metal pipe and leak. When smoke testing the fuel level has to be lower than the bottom end of the filler pipe.