Unless Jiffy Lube pulls out the OBDII, checks the code and clears it for free, don't take it there.
The light is most likely on from the cap being off (vapor emission code, can't remember what it is).
I think all TJ fuel filters are in the tank.
So, run the tank of gas with your additives (don't bother with "premium" anymore, won't do you any good). If the Jiffy guys will check your code, have them do it, if not, you can borrow a reader from Autozone to check/clear the code OR you can disconnect the battery for 10 minutes. The code will clear itself in some amount of time too. (some combo of engine running time and on/off cycles IIRC).
If it's running ok, shouldn't need a new filter. If not, well...