Just went to install new kn filter and notice a sticker on inside tray saying using a filter without felt top may be a problem. Anyone had any bad experiences with this filter? I had one on my 2002 and loved it. Thanks for any help. Jim

 

yes it may not seal right. the k & n filter will also allow a lot more dirt into the engine.

 

Says who? A K&N allows more AIR in, not more dirt. We've ran K&N air filters in dozens of our Fords and we are yet to have a single problem with any of them.
Octane

 

Heres the facts that are back up by independent labratory testing. Believe what you want, but K&N makes the best air filters in the world.
http://www.knfilters.com/facts.htm
You can spend $20 every 10,000 miles for the paper air filters. I'll stick to buying a K&N once and getting more power and better milage.
Believe me, if my engine fails due to dirt in the engine, I *WILL* make a post on here about it!
Octane

 

all reuseable air filters allow a lot more dirt into the engine. the oua's have proved it over and over. thats part of the reason why no car company recommends them .gm voids enigne warranties because of it. do a search all of it is there.

 

There have been a number of articles written on this, and sadly the aftermarket filters NEVER stack up to the stock ones, just the way it is. They do allow more particulates in then a stock one. The good thing is, we all can make our own choice and buy what you like or believe in.
Mike is spot on~!~

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…..See you on the boards.

 

think about it, if you want to allow more air in you have to???????? either make the filters thiner or make the openings greater... k and n have bigger openings in the paper allowing more crap to get through them... i run the wix air filters and i dont spend but 9$ every other oil change... if its dirty i blow it out once.... easy fix...

i run almost nothing but shale and dirt roads and our filters are rediculus

Matt

 

IMHO very rarely is the element itself the restriction to airflow, unless you drive gravel roads, and don't replace it regularly. The OEM filters of today have sufficient surface area to provide good airflow. The restriction (if there is one) to the engine injesting enough air will usually be found in the intake ductwork itself.
For example, I own (5) Fords...my 97 F150 4.6, and 02 Mustang GT 4.6 have restrictions in the ductwork, in addition to rather small ID air silencers poking thru the fender wall to draw cooler air. The replacement K&N air filters (cone filters) for these two applications do not fit very well in the stock air box (and I've told K&N about thier flaw, with no response), as they are manufactured to the small end of the tolerance concerning flange OD size so they are 'guarenteed to fit' all airboxes.
Unfortunatly that means they are a sloppy fit for most, and if you are not careful, don't seal at all. Dropping a K&N by itself into the stock air box of the Stang or F150 will not result in increased airflow to the engine over the OEM filter, it will just capture less dirt.
To increase air flow in these two vehicles, I replaced the entire stock systems with FIPKs & 80mm MAF...a noticable difference (30% larger intake dia on the FIPK). However, I will only run these with a dry charger installed over the K&N. They dry charger is either vacuumed off or washed at every oil change (3-4K). I do occasionally slip the filter off the MAF, and perform a 'white glove' test inside the MAF.
I've run these for about 30K on each vehicle, and the inside of the intake appears to be as clean or cleaner as my other 3 vehicles using the OEM paper filters. (Please note my other 3 vehicles running paper have 45K, 52, 76K mi)
I would never run the K&Ns on these vehicles without a clean dry charger, and a periodic cleanliness inspection.
And I don't do gravel...sometimes a challenge in IA...

 

Stay with the OEM paper filters....K&Ns were developed for races like Baja, where the OEM paper filters would clog very quickly.....Any extremely small
(if any) performance increase with the K&N is due to wallet weight reduction...

 

Jobo -

Check out http://www.bobistheoilguy.com/airfilter/airtest1.htm - it might help you decide not to run a K&N on the street.

Steve

 

I was experiencing a "rough idle" problem with my 01 Ranger 4.0, and narrowed it down to the IAC. When I saw how filthy and gummed up the old IAC was, my K&N filter hit the trash and the stock Motorcraft replaced it - how else did all of that crap make it to the IAC?

 

Most of the time the oil & dirt from the K&Ns contaminate the MAF sensor.

 

Well, that is an interesting test, and clearly shows results that are hard to argue with, HOWEVER... ALL the filters still let dirt through, dirt that is going into your engine. It is my opinion that the best filtering OIL filter is more important than an air filter. If you change your oil and filter regularly and use a quality oil filter, then it shouldn't matter if 32 or 54 ppm of dirt get in there. (I just pulled those numbers out of the air, they don't mean anything, just used to make a point.) We could test and debate until the cows come home, but at the end of the day, all the filters are still letting dirt in your engine. That is about the only thing that this test proves without a doubt.

 

That is a pretty general statement. Most of what time? I have used a K&N filter on nearly every vehicle I have ever owned (12 to be exact, 7 Fords, 1 Dodge, 1 Jeep, 1 Nissan, 1 Mercedes, 1 International Scout) and I have never had an issue with oil contaminating the MAF. I have seen it happen, but that was only because someone got a little over zealous with the oil when servicing their filter. I'd say I have done some pretty extensive "research" inadvertantly over the years regarding contaminating the MAF, and it has never happened. So "most of the time" is not really a statement of fact, only a generalization based on the theory that using a K&N will kill your engine one way or the other. Based on the test refered to in this thread, ALL filters let dirt into the engine, so ALL have the potential to foul the MAF.

 

You guys run what you will, it's a stock Motorcraft for me !