Comments on: K and N Air Filter Review: Save $1100 On Gas!

By: admin (Jason)

admin (Jason) — Wed, 10 Jun 2009 16:00:10 +0000

Carl – I thought you were referring to the filter in the bottom of the air box lid (hence the term air box cover). I haven’t noticed that filter before – perhaps it’s exclusive to the 4.7. The only functions I can possibly think of is that it either somehow protects the MAF sensor (which I sincerely doubt) or it’s designed to absorb moisture (also doubt that as well). I can’t think of any reason for it’s existence – if the air filter is doing it’s job, there’s no purpose in a second filter in the tube. I say remove it.

By: Carl Sampson

Carl Sampson — Tue, 09 Jun 2009 02:47:48 +0000

Thanks for the quick response. The filter I’m referring to is down stream in the air flow path, meaning the intake air has already been filtered by the air filter so I don’t know what your comment of “to block any really big “junk” from getting into the paper filter” means. Any big “junk” is caught by the regular paper (or K&N) air filter. All I can think of is that this second filter, filters the air again after passing through the “main” air filter but since it’s non-replaceable, it must not ever clog up with dirt so I still don’t understand it’s function. It would make sense that if this second filter was removed, air flow would increase as would the intake noise. Am I correct or am I missing someting?.

By: admin (Jason)

admin (Jason) — Mon, 08 Jun 2009 22:16:59 +0000

Carl – That filter has two purposes. First, it’s meant to block any really big “junk” from getting into the paper filter. Second, it’s a noise reducer. Removing this filter is an easy way to boost your stock intake’s power, but unless you also replace the stock paper air filter with something more durable, it’s a bad idea to remove it. Does that make sense (I don’t think I explained it very well)?

By: Carl Sampson

Carl Sampson — Mon, 08 Jun 2009 02:33:17 +0000

Hello,
I recently bought my first Tundra (2008 4.7 DC TRD 4X4) and it needed an air cleaner change so I went with the drop-in K&N filter. Feels and sounds like it has a little more power but I haven’t had the K&N installed long enough to check gas milesage. My question is, what is that cloth-like filter that is rivited in permanently to the air box cover? It seems like it would cause airflow restriction. If a cold air kit was installed, this filter in the air box cover would not be used so what is it’s purpose? I’ve asked two different auto part stores and the service manager at our local Toyota dealer and no one knows what this filter is for? Can it be removed to increase air flow?

By: admin (Jason)

admin (Jason) — Sun, 03 May 2009 21:13:17 +0000

tmac – Sounds great man – 1 mpg is awesome. That GF sounds OK too…it’s love when they buy stuff for your truck.

By: tmac

tmac — Sat, 02 May 2009 05:27:11 +0000

actually i hafta make a correction on that i didnt buy cai my girlfriend bought it for me for xmas..
god bless her

By: tmac

tmac — Sat, 02 May 2009 05:25:08 +0000

bought the k&n cold air intake and must say im impressed the sound is awesome so much more aggressive than the stock sound of the truck (wich sounds more like a camry).
power and throttle response is improved and i gained 1 mile per gallon, how can u complain about that…

By: john

john — Sat, 04 Apr 2009 02:56:32 +0000

I had a K&N filter clog up my map sensor a few years ago. Maybe I oiled it to much or oiled the wrong side. Whatever happened it scared the shi?? out of me cause I thought my truck was ruined. Kept shooting carb cleaner untill I somehow managed to unclogg something. May be someting I did but I changed to paper fram filters and have stayed with them since.

By: admin (Jason)

admin (Jason) — Sat, 10 Jan 2009 05:14:38 +0000

Mickey – Good point.
Jim – A factory-oiled K&N cotton gauze filter shouldn’t be clogging MAF sensors…yet the rumors persist. K&N sponsored an independent study that showed fairly conclusively that their filters aren’t clogging MAFs, so we stand by our assertion that this is at best a rare occurrence.

By: Mickey

Mickey — Sat, 10 Jan 2009 01:05:32 +0000

My comments above.