Salesman said "Check Engine Light" was on because of Air in the Gas Line which occured when filling gas tank and that light will go out after I use this tank of gas and fill it up again. Does this make sense?

Often if the gas cap is not put on tightly the Check Engine Light will come on. Very common. But make sure that is the problem, if the light persists be sure to get it checked out

Thanks for post. I've done everything I've read here to fix problem. But, light is still on; waiting to hear from salesman to see what the next move is. I'm afraid dealership won't do much, I bought it used and as is. But, I didn't expect the engine light to come on in 3 days. Hopefully, dealer will help. They are well-known in the area as new car dealer.

i would go and tell them that it came on three days after you got it! thats crap!!!

accuse them of having reset it just to get it off the lot, and once it got off the lot it came back on.

Thanks for suggestion. I may have to give that a try.

has the problem been resolved yet?

Dealership had car over night. According to them engine is fine replaced a sensor. But, after I've driven car & I get out, I can smell a burnt smell. I told dealership this. Salesmen said 3 mechanics worked on car and ENGINE IS FINE. Only time will tell. Thanks for reply.

that may just be some sort of fluid spilled on the engine...if it doesn't go away soon, you may need to pay them another visit.