[Crazygirl]

I have a 2003 Camry XLE with 220,000 miles on it. Despite that, it has been really good with the gas mileage, averaging almost 400 miles on a tank of gas.
However, last Sunday (two days ago), I had my hubby replace the air filter since I don't know when it was last replaced by the previous owner. I got a cheap brand at WallyWorld.
It's in the casing, but he had a little trouble fitting it in and getting the casing closed. I can see a little bit of the white edging of the filter peeking out between the two parts of the casing, which I don't recall seeing when the previous filter was in.
Since Sunday, my little darling has used almost a half-tank of gas, even though I haven't put any more miles on it than I routinely do. I can drive on the freeway and actually see the difference. Wow.
We have not seen any evidence of any leaks, and I don't smell any gas fumes. Is it just a coincidence this could happen and I should have a mechanic look at it, or could a poorly fitted filter actually cause this kind of problem with the fuel consumption?