using K&N air filter and Check Engine Light?

Hi, If you sprayed too much oil on the filter, you know what can happen.

well the filter was new, so i did not have to spray anything on it ... just took it out of the box and installed it

something tells me it is the O2 sensor that needs replacing as the gas mileage has been a bit low lately ... approx 19 MPG city with A/C in use at all times ... could someone kindly post instructions for O2 sensor replacement?

also does 2005 Forester have one or two O2 sensors?

much appreciate!

Hit up Autozone before you start blindly throwing parts at the problem. They should be able to read your CEL code for free, provided they're not too busy, so you have a better idea what symptoms have set the code instead of guessing.

Perhaps the computer is not happy with the readings coming from the MAF sensor since installing the 'high flow' filter?

~Brian

Hi, I have a OBD II interface box for my laptop and got freeware OBD reader(software). Very handy to have.

K&N not likely as cause. Mine's been on there for 70+k and the one time CEL was "fuel level sensor" Dealer cleared it and it never came back

Can you post more info the OBD II device and the freeware reader (maybe a link to them?)

thanks

Same thing happened to me with a 97 Legacy.

The filter was a really tight fit, the case was hard to close again. In cursing and struggling to get the filter in the housing, I managed to dislodge a vacuum hose under the air cleaner intake.

The engine ran rough, wouldn't idle, and I didn't seen anything wrong. My mechanic laughed at me, found the dislodged hose in seconds and it's been a fairly happy car since.

Mike