Reviews of K&N air filter

In my experience they are a waste of money with risk of fouling MAF sensor. I’ve tried them in my diesels and gassers. I never once wasted my time cleaning and re-oiling a K&N. I just threw it out and went back to OEM.

I ordered and installed a k&n air-filter in my 19 Jetta r-line 1.4 and it seems to have a little more pep.

The k&n air filter is significantly thinner.

I personally have the k&n filter on my 2010 Forester and recently got the reusable cabin filter and have not had any problems.

I have one in both my Forester and wife's Crosstrek. Performance increase? Meh. On my XT it didn't matter, but I did find that the Crosstrek's acceleration from a stop increased nicely. I've had one on my Jeep for over 200k miles with no problems.

I had a K&N air filter in a NA engine VW. Some particles do get through as I could feel grit on the inside of the intake pipe past the airbox. I washed and oiled the filter per instructions.

I used K&N drop in filters as well as the K&N Typhoon intake on previous cars. I don't think the K&N drop in filter makes more than 2-3 hp. The K&N Typhoon intake might make 10 hp. It does sound good though (like all open air filter intake systems).

I use K&N filters on 3 of my vehicles - my '74 G30 350 V8 Chevy Van tow vehicle, my '93 RX-7, and my F2000 racecar. On the racecar, it is a required spec part required for all F2000 cars using the Zetec engine. In 14 race seasons (~100 races) of use it has caused no issues. My engine builder says my engine always looks good when they get it for a refresh. On the RX-7, it was part of an induction upgrade (the OE intake was very restrictive) and provided a noticeable power increase. It has caused no issues in the ~60K miles it's been in use. On the Chevy van, the OE air cleaner was way too small and restrictive for towing purposes. The K&N provided a significant benefit in gas mileage and power. It has been in use for ~200K miles and has caused no issues. YMMV.

I have a K & N filter in my 2016 cx9, it's been there since about 10k miles, now has 93k miles on it. I feel I picked up about 1 mpg with it and it does feel peppier.

K&N filters are great for the price. Very little gains. In my opinion the engine felt a little more responsive and maybe had a little more top end. But nothing to write home about.