09 Caliber help

Daughter has. 09 Dodge Caliber, keeps throwing a P456 code, small evap leak. I have replaced the vapor canister purge valve and the vapor leak detection pump. Those were relatively cheap to do. From what I can see the hoses all look good, but the code came back. Is my next step the vapor canister or is there something else I can look at without having other diagnostic equipment, I did clear all codes, the check engine light stayed off for 2 days. She did have a gas cap warning but replaced it with a cheap one, the gas cap light has not returned
Thx