I was hoping someone on here could give me some advice. I have a 2006 CC LE with a check engine light on. A little history. It came on about 2 weeks ago and my wife had just put gas in it. I tightened the gas cap and the light went off on my way home from work. It came back on two days ago and I had the code read at the local autoparts store, gross vacuum leak, AKA gas cap. I tightened it and the light stayed on. I put on a new gas cap and the light is still on. Will this go off on its own or do I need to reset it? Could there be another problem I should be looking at. Any help would be appreciated.