Change to high quality filter lead to drastic drop in fuel efficiency

[N9QGS]

I tried a K&M oiled filter, and after about a month or use was disappointed myself with the lack of MPG I was obtaining, so I switched back to the Toyota Air filter and everything was fine again. Im not sure how much learning or tolerance are in these ECM, but I personally wont try an oiled system again cause I heard that also can fowl other things down the road, don't know if myth or not. I wish you luck with your decision and outcome.

[1stToyota]

Originally Posted by N9QGS

I tried a K&M oiled filter, and after about a month or use was disappointed myself with the lack of MPG I was obtaining, so I switched back to the Toyota Air filter and everything was fine again. Im not sure how much learning or tolerance are in these ECM, but I personally wont try an oiled system again cause I heard that also can fowl other things down the road, don't know if myth or not. I wish you luck with your decision and outcome.

They say it's a myth, but logic says different...with a little over-oiling the oil has to go somewhere, MAF meter (yes, w/ heated wires ) is downstream within just a few inches from the filter.

[RedRide]

I have been using a K&N air filter on my Celica (in the Stock airbox) for the past 6+ years with absolutely no problems.

The oil problem myth is perpetuated by maufactures of competing protucts.
You really have to be mentally deficient to over oil it and a little common sense goes a long way.

I have have had zero MAS problems, etc.

When I get around to it, I'm putting one in my Yaris.

BTW even Toyota sells a K&N type filter. It's called a"TRD air filter" So, even Toyota says that they are not a problem.