K&N air filter question

[john gorsuch]

Well after I bought my 2017 xlt with the 2.3 L ecoboost, I decided to get the K& N drop in filter. I didn't think anything of it because I have bought these in the past with other vehicles. Recently I have had some issues with hesitation and tranny issues with shifting problems with reverse and back to drive, and initial take off. I was doing some research and one video related to it not being actual tranny issues, but from the throttle body and sensors. So I decided to put my stock filter back in, and now the throttle response is better, and the tranny is shifting like original. So my question is, are these engines sooooo tuned with the turbo and such, that any change from stock can lead to these odd issues?? I did nothing different other than change the filter, I didn't loosen any clamps, pull any sensor wires, nothing just open and closed the filter box. any suggestions?

 

[RandyH2]

Perhaps the K&N filter was not "perfect". A dirty filter (or over-oiled) can cause various problems including hesitation. I don't know if decreased power would impact shifting but with the systems being so interconnected I wouldn't rule it out.

Regarding K&N filters: If you are not running a race or off-road motor which will see frequent service, high moisture, etc., there is likely no benefit and definitely potential harm in using a foam and/or oiled filter on a passenger vehicle. Those "fancy" filters don't filter as well and the drop-in ones probably don't even give a noticeable improvement in performance though I could be wrong as I have not used one in decades.

Your engine has VERY tight/precise clearances, runs at high pressure (note that a slight increase in compression ratio has a much larger effect on internal pressures), has two turbos, and therefore any dust/contaminates getting through the filter lead to increased wear, more so than on engines from a decade ago, let alone 40 years ago.

Worth considering:
http://www.nicoclub.com/archives/kn-vs-oem-filter.html
And if you need to see debate about it: http://boards.straightdope.com/sdmb/showthread.php?t=688436

 

[RandyH2]

 

[CDW6212R]

I agree that it was likely the oiled filter, or just a slight looseness of the clamps holding the air cleaner piping together.

The air filter is very critical to oil condition, and more so for a boosted engine. A poor filter that doesn't clean well, will make the oil turn black much faster. K&N filters are among the worst for air cleaning, I used to use them until I learned this.

The paper filters as pictured do clean very well, but they also don't hold as much volume, thus they get clogged faster. That ends up hurting performance and fuel economy. The gauge or other not paper filters do last longer. If you can keep up with regular changes, the paper filters will do great, but cost more.

I like the Amsoil air filters, because they clean very well, and they also last a long time. Their EA line(OEM sizes are now obsolete) are made to be cleaned(vacuum carefully every few months or a year, and they could last for years. I wish they didn't stop making them, they now only make universal sized units, lots of cone sizes. I have one in three of my Fords, and they might last me for ten more years depending on my mileage etc.

I suggest tossing the K&N filter, I didn't like my oil becoming black right after changing it. Now my oil stays transparent for a long time. Regards,

 

[Odrapnew]

Correction: In the test above, the K&N had the 2nd lowest capacity(just ahead of the Amsoil). The “paper” AC Delco had the highest capacity.

This quote sums up the K&N performance.
“Compared to the AC, the K&N “plugged up” nearly 3 times faster, passed 18 times more dirt and captured 37% less dirt.”

I also ditched the oil/gauze style after I started my current job learning the issues with those “high flow” filters. For my Mustang, I have whatever came with the mass air meter. In my Explorer, I’ll just run any quality brand paper type filter.

Another comment, don’t change your filter too often. A filter is least efficient at removing debris when it is clean. As it loads, it becomes more efficient. Most people change filters too often. I changed my Sport’s air filter @ about 45k miles and didn’t look too bad…but looks can be deceiving. Just because it looks clean/dirty doesn’t mean it is.

 

[Centaurus5.0]

One problem with that air filter comparison is the Amsoil filter (TS123) is a foam filter, not an EaA type which would have made Amsoil at the top. But it goes to show that a quality "paper" filter does what its suppose to do. K&N has an unending advertising budget due to people keep on buying them because they believe their advertising (go figure). They found a way make people buy not only an air filter that that doesn't do what it's suppose to do (filter air), but also have to use another product with it (K&N oil) which they can sell and make more money as they gunk up the mass air meter (either from the oil or by letting dirt pass through from poor filtration). All the while people believe now they have a K&N (they have a cool sticker on the box to prove it!) it elevates their car from a lowly stock classification to a "high performance" vehicle because "performance begins with K&N" and are now a car length quicker than stock car. Frank Pedregon uses one one his 5 sec, 300mph dragster to get "the edge" on his competitors ya know, and he wouldn't lie to you.



I think everyone has bought one at one time on another when looking to improve their vehicle. Had one in one of my foxbody 5.0 back in the day. But my feelings now are if I see someone with a K&N sticker on their ride or they list it as a performance mod, they are a noob. We all have to start somewhere I guess.

 

[Centaurus5.0]

I suggest tossing the K&N filter, I didn't like my oil becoming black right after changing it. Now my oil stays transparent for a long time.

This is the truth.

 

[reserved50]

I would never personally run a stock replacement K&N air filter.

The only K&N filters I run are for modified engines or engines that need custom piping. I usually clean the filter once every few years if I have nothing better to do, trick is to get the largest cone filter that fits then let it plug up, yes I said let it plug up . What this does is not allow the smaller particles of dirt to enter the engine while allowing more air flow compared to factory due to the over sized filter. This way also stops excess filter oil from getting on the MAF sensor if the vehicle is equipped with one.

 

[Centaurus5.0]

Why wait a year or two for it to get dirty to achieve maximum filtration when you can roll it in the dirt when its still new and have it right away?
Make sense?

You could use the same reasoning for a paper filter. If the factory one is a restriction to air flow, put a larger one on by installing a bigger airbox from another vehicle or a bigger cone. But I'd wager a oem paper filter still filters better than a dirty K&N.

 

[Odrapnew]

Why wait a year or two for it to get dirty to achieve maximum filtration when you can roll it in the dirt when its still new and have it right away?
Make sense?

You could use the same reasoning for a paper filter. If the factory one is a restriction to air flow, put a larger one on by installing a bigger airbox from another vehicle or a bigger cone. But I'd wager a oem paper filter still filters better than a dirty K&N.

While I'm sure that's partially a joke, it does make sense as long as you keep the clean side clean.

If the paper used in the OEM filter is anything like we use at my company, the initial efficiency of the OEM is well above the full life efficiency of a K&N.

I have a Pro/M 80mm meter and filter like that one on my Stang. I don't think I've cleaned it ever, but I only drive it 3k-5k miles per year, so it's not like it has a lot of miles.

 

[CDW6212R]

The better a filter does filter, the finer the media is, so it will fill up(not work well) faster. That's what makes the paper filters work better initially, and become a restriction quicker. The fabric kind have a much better capacity because it's far deeper from one side to the other of the material. The K&N filters are a much more coarse material than any paper filter, but also a lot more than the Amsoil fabric in their best EaA filters.

I like those mostly because they are strong enough to be vacuumed. The point isn't to be able to suck all debris out, just to keep the big stuff from covering the outer surface. I use a common paper filter when rushed, or for a new purchased vehicle. Those are available everywhere, while the best kind are often tough to locate and take longer to get etc.

 

[Odrapnew]

The better a filter does filter, the finer the media is, so it will fill up(not work well) faster. That's what makes the paper filters work better initially, and become a restriction quicker. The fabric kind have a much better capacity because it's far deeper from one side to the other of the material. The K&N filters are a much more coarse material than any paper filter, but also a lot more than the Amsoil fabric in their best EaA filters.

I like those mostly because they are strong enough to be vacuumed. The point isn't to be able to suck all debris out, just to keep the big stuff from covering the outer surface. I use a common paper filter when rushed, or for a new purchased vehicle. Those are available everywhere, while the best kind are often tough to locate and take longer to get etc.

In the case of the below side-by-side testing, that is incorrect.
Here's a link to the article for the testing from the graph above(hope this is OK): http://www.nicoclub.com/archives/kn-vs-oem-filter.html

The K&N and the Amsoil filters tested have the lowest capacity(and lowest efficiency). Just because a filter is more efficient, doesn't mean it holds less dust. There are a lot of factors that affect the performance of a filter and the K&N is designed to be low restriction while throwing efficiency and capacity out the window.

Depth loading, as we call it, is detrimental to dust holding capacity, especially in out in the field.

The Amsoil EaA has a nano fiber layer on the top of the ‘coarse’ media. That fine fiber layer actually helps the debris shed from the filter under regular vehicle usage. If the debris is depth loaded, it’s not as likely to “fall out” of the filter during normal operation, so it continues to build up inside the filter media until it’s plugged. The nano fiber also improves efficiency, especially the initial efficiency. Most of the gains from nano fiber is seen in the field. The lab testing doesn’t do it justice in regards capacity. I do get a chuckle out of the Amsoil brochure where is says "a major break-through in filtration technology.." I know nano fiber technology has been around for over 30 years and used in off-road construction equipment around the world, so it's nothing new.

 

[Centaurus5.0]

Pro-M 80 comes with a "lifetime" filter. I used to think its was an Amsoil/Injen Ea filter but it's not.

If you look on the right it's printed "Don Anthony Designs Houston TX". I can't find what kind of filtering medium they use. One reason they say it's a lifetime filter could be the Pro-M doesn't have a metering wire in the direct air stream which keeps dirt/junk from collecting on them. Just a theory. Could still be the same medium amsoil uses for all I know. At least they didn't use K&N's "Million Mile Warranty" marketing BS.

I believe Don was refering to the depth of the pleats. Most dirt will collect in the bottom folds first then accumulate from there while still drawing in air from the cleaner top fold/pleats. Amsoil filter and OEM Pleats are much deeper/thicker than K&N which rely on the oil to capture the dirt. This of coarse attracts dirt and gunks up the entire filter.

To get the longest life and flow with the least amount of cleaning would be a quality cone filter with a pre filter inside a box.

Or, you could just replace the oem filter every couple years for $10-$15 and find something else to obsess over.

 

[CDW6212R]

...


To get the longest life and flow with the least amount of cleaning would be a quality cone filter with a pre filter inside a box.

Or, you could just replace the oem filter every couple years for $10-$15 and find something else to obsess over.

Ditto, I tend to go for the longest life solutions. I hate having to do oil changes every month or two depending on how many vehicles I'm using etc. That makes the filters and fluids more attractive that require less labor, less often. I don't mind cleaning an air filter every once in a while, if you have to buy one often it adds to the list of to do items for car care. I'm plotting on soon having two external filters for each, my oil, trans, and PS fluids. For work I'm abusing the PS pump/fluid/rack more than I'd like. Extra fluid and a bypass filter will make the fluid cleaner and last a year for sure. That's worth the trouble in the long run. I'd love to only do fluid changes just once a year, when I want to, say in the Spring.

 

[reserved50]

not sure if you've ever worked on a car but tossing in random air boxes at will in a tight engine bay doesn't work, there would be no point explaining it either. I hope you understand. Point was its not good to frequently clean a K&N filter, weakens the structure and lets in unfiltered air.

Why wait a year or two for it to get dirty to achieve maximum filtration when you can roll it in the dirt when its still new and have it right away?
Make sense?

You could use the same reasoning for a paper filter. If the factory one is a restriction to air flow, put a larger one on by installing a bigger airbox from another vehicle or a bigger cone. But I'd wager a oem paper filter still filters better than a dirty K&N.

 

[CDW6212R]

The K&N filter doesn't clean air well, whether it's clean or dirty, new or old. There's no point in discussing a filter that doesn't filter well all of the time, and no let's not see how clogged one has to get before dirt stops going through it. An air filter needs to clean the air at all times, when new and old.

This horse is dead, I'm leaving it buried. Night,

 

[Centaurus5.0]

not sure if you've ever worked on a car but tossing in random air boxes at will in a tight engine bay doesn't work, there would be no point explaining it either.

Still makes more sense then most of the homemade hack job "CAI's" I've seen over the years.

K&N=Noob

There would be no point trying to explain that any further either.

 

[reserved50]

please do your best to explain, I wanna learn from you. I've been doing it all wrong in my noobyness, now that I rethink this. If not I will try and stock up on random large factory air boxes, any certain models I should look out for that have good flow characteristics?

Still makes more sense then most of the homemade hack job "CAI's" I've seen over the years.

K&N=Noob

There would be no point trying to explain that any further either.

 

[Centaurus5.0]

Actually, I was thinking about 5.0l vehicles (2nd gen explorers/ fox mustangs/ f150) with larger engines 331-460 tha have room under the hood and not 5th gen explorers when I said that, so yeah, I see your point there. There is more room under the hood of a geo metro than there is on the 5th gens. So, to make it fair, I'll give you that one.

But I still don't see how you think a dirty air filter is better than a a clean one. I guess you don't clean your underwear for years for the same reason in that they filter farts better than clean ones do.

Must have been the carbon monoxide talking?

 

[reserved50]

no no, I said an oversize cone filter once dirty will still flow well but not allow as much debris by... ignore that, it went over your head as does most info that's gets passed around by the internet by people that feel they have been informed. I know you meant well and we all appreciate it in the 5th gen forums.

I still need to know what air filter boxes to use that have this fabulous flow you speak of, part numbers you have saved for these outdated oversized engine blocks that require this kind of air flow would be nice. Do you have any pictures of your custom work, I would absolutely love to see what you're capable of.

Did you ever wonder why your gen Exploder had side exit and rear exit exhaust and one was slowly discontinued aftermarket and or factory? Get back to me when you know that answer since it maybe harmful to your health