K&N AIR FILTER

Hello, It was time to change the air filter on my 2020 TRD ORP and I decided to go with the Reusable K&N filter. Now there is a slight whistle sound. I've double and triple checked all the normal areas and it appears to be snug. Anyone else experience this?
Thanks

 

No leaks, that’s the sound of added horse power! JK, I heard it on mine too.
I used that K&N for a while but got tired of the cleaning/oiling and the time waiting for it to dry. So I went back to OEM filters.

 

If claims are to be believed, and the K&N filter indeed breathes more air than the factory filter, it isn’t unexpectable to experience different sounds of that faster air. I took off the silencer in my Cummins Ram I liked the whistle so much.

 

I wouldn't use a K&N airfilter on a 4runner. These aren't sports cars, and they don't do as good a job filtering stuff as the OEM filter which is more important on a vehicle that might be driven down a dusty road.

I also have a few horror stories from buying a 4runner with a K&N airfilter and all the trouble it caused me. There was no difference in performance either, if there is its not worth the decreased filtering ability that is so important to a vehicle driven off road.

Make sure its not the filter, it could be one of the seals you opened to install it

 

Thanks all. All it was purchased for was for the idea of cleaning and reusing and not buying one over and over. I might consider taking it back.. Seems like most people on here don't like them or don't think they function well for the 4runner..
Thanks

 

Junk filters. Put in a genuine Toyota paper filter.

 

One more thing. Some people have reported problems with the MAF sensor and throttle body when using a K&N. Perhaps due to user error by oiling the filter too much.

 

Cool, thanks.

 

I have k and n filters in all my vehicles and have for years. Never had an issue. Just don't oil them too much. I keep a paper filter for each vehicle as well so when I clean/oil the k and n I can swap in the paper filter and not be stuck waiting for it to dry.

 

Use AEM reusable air filter instead.

 

Thank you, I'll look into it.

 

I'm not a fan of reusable filters. I choose long term reliability vs save money on reusable ones. I go with good paper filter and change as needed. Other than my preferred Denso I have used FRAM Extra Guard filter as well. No complaints and they are pretty cheap.

 

Oiled filters are the bane of many a mechanic. They should be banned. They create so many problems for less than no benefit.

The Toyota engineers balance mileage, HP and noise when choosing the filter size and makeup for the engine. You can get a tiny bit of HP from a "performance" filter but will sacrifice MPG and Noise.

Usually the HP gained is no where near the claims K&N makes and can be gotten for free by taking a dump to reduce weight prior to driving.

 

On my 4runner the last owner put WAY too much red oil on my air filter. The third gen 4runner has a grid pattern at the bottom of the airbox, and each one of those little squares was filled with a little red oil because the oversaturated filter dripped the oil. Not only did this red oil sometimes splatter up on my new paper filter, but it also captured dirt and dust and made an oily mud that clogged the drain holes and was very difficult to clean out (thanks to that grid pattern). That was user error, but its not hard to see how someone might do that.

Early vehicles did use oil bath air filters, supposedly they were just as effective (but I don't see any tests validating that) and could be reused. But the filter element sat above a pool of oil that would collect dirt that was dropped by the oily filter element. They were higher maintenance, especially in dusty environments. And the design of them has several important differences that cant be replicated by a K&N filter. The oil bath filter was phased out when carburetors were still found on a vast majority of cars, I don't imagine that a modern Maf sensor would work well with a dirty pool of oil that might me sprayed up by the rushing air.

 

My buddy gave me one for my Pro-4x Xterra (had prior to my T4R) and it fouled my MAF and threw a code within 24hrs, the K&N was BNIB. I cleaned the MAF and the throttle body (which was long overdue), dropped my paper filter back in and was good to go.

 

With modern cars and advanced paper filters, I’m surprised that oil impregnated filters are even considered.

I would think that even a properly serviced oil impregnated air filter would allow residual oil into the intake plenum.

 

One word in filters: Wix