I have had the same problem as you with the evap codes, small, medium, and large. I have been fighting with it since last October. I did install a new gas cap, but the codes kept coming. I would try to clear the codes by disconnecting the battery cable, then cables, for a few minutes, then a few hours, then overnight, then the positive on the negative, and everything would be good for a couple of days then on came the CEL and I would start all over again. A few weeks ago I finally got sick of it and took it to the local mechanic who advised me to take it to the stealer so they can do the smoke test, so I said ok. Well, before I left he wanted to check the code himself so he hooked up the OBD II code reader, read the codes, and cleared it out. Now three weeks later the CEL has not came back on! Maybe the new OEM gas cap fixed the problem after all? I do not know if my situation was a fluke, but the battery thing must not have worked for me, so if you have more issues with the light you may want the code cleared by a OBD II reader. ScoobyThanks man.
I am having the same issues with the P0455 code. I don't see anything wrong visually looking at my gas cap. Do you recommend just changing it out for a new one? Is there a way I can check to see if my gas cap is broken?
I have gone through the tubing to the EVAP system and it looks fine. I disconnected and reconnected everything this afternoon. I am going to drive the Jeep tomorrow to and from work to get everything reset. I have the battery disconnected today.
If the code comes back after driving tomorrow, what should I look at next? Should I just take it in to the dealer at that point? Thanks!