Just thought this may help others. my process took about a month to fighre out.
I had been stuffing my fuel tank for years and got away with it. I had no idea doing so could foul up the EVAP system. Stupid is as stupid does!
It finally caught up to me, check engine light came on after an over fill. I pulled the code and came up with 2422, EVAP sytem blockage, valve not working etc...
over about one months time i learned how the system works and began to try and trouble shoot, after pulling down the canister from under the car(drivers seat side) 2 times and manually checking all valves and selonoids etc... I noticed lots of liquid coming out of the EVAP vent shut valve hose. while most cars set this code due to spider webs/nests in the vent line, mine was not this issue. I pulled the canister which is number 10 on the honda parts sclematic under the" fuel pipe heading" this canister is under the hood on the firewall. this canister i assume to be the charcoal cansiter. it was loaded with liquid. I blew it out multiple times with my air compressor. then let it sit in the sun to heat up and hopefully evaporate / dry out the charcoal.I re installed everything. drove 100+ miles out to Orient Point Long Island with the check engine light remaining off. it used to come on after about 3 miles after clearing the code, so i will consider this a successful fix.
hope this helps anyone who has the same issue. I did not have to buy any new parts. lesson learned , DO NOT TRY AND STUFF AN EXTRA 1.5 gallons in the tank.

 

What year Fit did you have? My '08 fit is throwing P2422 and when I removed the vent shut valve hose I had some water come out. Didn't smell like fuel or anything and I never top off, but at this point I want to get this code to go away and will check anything if it might be the answer to the problem.

 

 

Thanks! I'll check those two things and see what I come up with.

 

No water in the charcoal canister you mentioned, but a thick spider's nest in the connected drain tube. Taking it out today, hopefully that solves my issue.