Beer makes me pee
Working on a car for a friend trying to get it inspected. It is a 2006 pacifica. Got the engine running right with new lifters and spark plugs. Then the p0420 code popped up. I have a autel scanner and it showed a bad converter, so I replaced that and the o2 sensors. Now showing missing gas cap. Replaced the cap but it is still showing the same code. I am looking for a diagram on how the vapor system works but cant find anything.