Malfunction indicator lamp

[BJack19]

My Malfunction indicator lamp turned on a week ago, a day after I put gas in the car. Then the next day the light turned off. Yesterday I put gas in the car, and this morning the light turned on again. I checked the gas cap, like the manual said, and it's securely tightened. Why would putting gas in the car make this light turn on, then turn off. Any suggestions, on what could be causing this?

Update;
On my lunch break the light turned off again...

[C25A1guy]

This is a US specific issue. Its because for US emissions, there's a fuel tank sensor required. If the gas cap isn't on tight enough, you'll trip a MIL. Try giving the gas cap a few more clicks, and if its still no good, check the rubber seal on the cap and if its bad, you'll need a new gas cap.

[BJack19]

I took it to the dealer I bought it from and apparently the machine they hooked it up to is showing it has to do something with the Cam and timing sensor. He thinks putting gas in it is just a coincidence. He said it could have something to do with the oil being to thin and it's burning to quickly. (The oil was slightly low). He recommended changing the oil, and putting a 10w oil over the recommended 5w. Does this seem like something that would be worth trying? or should I take it somewhere else? This doesn't really make sense to me, and I would rather get this fixed, rather than do damage to my car if it's something more serious. And I don't want to waste money on new oil if it's not going to do anything.

Right not I have 5w 30 Mobil 1 Synthetic oil and I put it in about 1,500 miles ago....

[C25A1guy]

Try switching over to Eneos or Torco oil (I carry both) in 5w-30 first. The current formulation of Mobil 1 has been crap.

[HardcoreRsxS]

If you do switch out the oil, I would send the oil to a 3rd part oil analysis laboratory (i.e. blackstone or polaris) and have them analyse the oil. Then I would send the results (usually same day they get them) to mobil one for their own analysis