My dash keeps saying but my gas cap is on and tight. Anybody else had this problem? Do I need a new gas cap or could something else be wrong

 

It might just be another emissions code. Catalytic converter maybe? I'm just snowballing, I'm no expert by any means. Just a redneck with a wrench.

 

It could be a bad gas cap or an evap canister leak. Have the cap tested or replaced and see if the code resets itself.

 

Do you have a stored code/check engine light? Were you off roading?

 

Bad Problem on the 2007's I had the same issue it took a replacement of the entire emission system to correct the issue. That was when it was still under warranty.

 

Have you driven it much since the light came on?
The jeep needs to travel a certain distance and run some checks before it can clear the code itself ( if it was just the gas cap having been left off).

 

Don't we all just love modern technology? The more we move into the future, the more complex the problems. Man I loved the old days. Simple engines, no computers, simple fixes. Anyway, your problem is not real complex. I had the 'gascap' light come on yesterday for about an hour. Then it left. Why? Who knows... So, I took it off and put it back on and it went away. I haven't a clue why. Some say it's a slight leak in the system or a hose that 's not on tight. It's going to take a check of everything from the cap to the engine where the hoses end to figure it out. There is a thread here that talks about a hose next to the battery which can get a small hole from contact with the battery and this could cause it. Just check all you can and if that fails, the dealership is probably your next step. Good luck.

 

AMEN to that. I have often wondered if you could take an older engine (pre all the electronic BS) and make it work in a newer vehicle.

 

In Md the engine you swap in has to be from the year of your build or newer. Bummer.

 

Just in front of the negative battery terminal are 2 tubes that can rub together and wear a pinhole leak into one of them. This caused the evap/emissions codes I was getting. You might check that. I taped the worn spot up and no more codes.