Can an air filter make THAT much difference?

[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?

[Brian R.]

It seems strange, but there have been stranger things happen. I would check around the air filter housing for a disconnected hose or electrical plug. Pull the filter and make sure there is nothing blocking the airflow (paper, leaves, rag).

I would say you should not scrimp on consumables for cars, but everyone has their own priorities. If you don't find something amiss, get a high quality filter, ACDelco, Toyota, Purolator, etc.

[Crazygirl]

So I had my hubby replace the filter, again, with one I bought from Autozone. It looks like the other one, but for some reason it was easier to put this one in.
I'm going to keep an eye on the fuel level today, but if that change doesn't affect how fast the gas is burning, would anyone have any other ideas of what it could be?
Like I said, we haven't seen any leaking or smelled anything, she's been great so far as gas consumption goes up until this week. And then all of a sudden, it's disappearing like something is sucking it out with a straw.

[Brian R.]

You know, it wouldn't be the first time someone was syphoning gas out of a car. See if it goes away...

[Crazygirl]

I can guarantee it's not gas siphoning, lol. I was actually seeing the needle moving slowly as I was driving down the freeway. And my husband crawled under the car to check for leaks as soon as I realized something was going on. I only wish it were something as simple as siphoning, since I have a feeling it's going to need to be checked out at a repair shop.

[Brian R.]

Could it be your gas gauge?

[Crazygirl]

It may have been the air filter. Once we replaced it with a different one and my hubby was sure everything was tightened down correctly, it seemed to work like before. Now I'm back to getting about 375 miles per tank. Thanks!

[Brian R.]

Thank you for the follow-up

(Maybe he forgot to take the plastic overwrap off of the air cleaner element... jk)