K&N Addresses MAF

[Ghostrider 310]

I decided to ask K&N if they had heard about the MAF failure claims in the Boxster. I thought everyone might like to see what they said.


Dear XXXXX,



At this time, K&N is unaware of any evidence that K&N air filter oil from a K&N air filter can damage or cause the malfunction of a MAF sensor, regardless of the make of the vehicle involved. K&N takes seriously any claim that one of its products is incompatible with its designated application or can damage or cause the malfunction of any automotive component. Such claims are thoroughly investigated and, when appropriate, testing is undertaken to determine their merit. In the case of MAF sensors, ongoing tests have shown that contamination from K&N air filter oil has not caused any failures or malfunctions of the MAF sensors in the test vehicles. K&N is aware that MAF sensors can become contaminated for a variety of reasons, unrelated to a K&N air filter (such as backfiring, blowby, leaking airbox or leaking intake duct) and that various methods have been used by some service departments and repair shops to clean a dirty or contaminated MAF sensor, such as spraying with an appropriate cleaner. K&N has not completed any tests as to the efficacy of such a process and, therefore, does not officially endorse or recommend any cleaning process. However, if given the choice of either replacing a MAF sensor or cleaning it, K&N recommends that the consumer ask his or her automotive dealer to attempt cleaning, before replacement. It should be noted that the presence of contamination does not mean the contamination was the cause of the MAF sensor failure. Sensors can fail for electrical or mechanical reasons, unrelated to any visible contamination.

For more information about filtration and to answer any other questions you have about K&N products, please visit our website at www.knfilters.com and go to and our FAQ page at .

Thanks for writing,

Looks like K&N had this letter proof read by their legal department, that's for sure!

[RandallNeighbour]

blah blah blah. Sounds like this guy went to law school.

[Ghostrider 310]

Don't shoot the messenger, OK Boys?


I told the guy that K&N was being discussed on a variety of sites as the cause of MAF failure and that they need to provide evidence if they intend on keeping the Boxster business. I thought this forum was for all of us to learn as much as we can about the car and it's available accessories, if I got that wrong then by all means, blast away, here's the guy's final note.


XXXXXX,

We are doing the testing on MAF sensors so that we can prove that the slander is just that. This is a test that we are in the middle of conducting and we will post the results soon. Feel free to check our web sight for newly released news.



Thanks for writing.

Nick R. Selle

Technical Support

K&N Engineering

nicks@knfilters.com

Originally Posted by Ghostrider 310

Don't shoot the messenger, OK Boys?

No shots fired here, ghostrider, sorry if you thought I did. Thanks for sharing your communication with K&N with the forum.

[Ghostrider 310]

Just trying to help all other Boxster lovers. I have a K&N, I have had no problems, but if there is a proven propensity to ruin MAF's, then I want to remove it.

[RandallNeighbour]

Ditto for me. We're not aiming anything at you, friend.

I'm always surprised at how companies try to explain away things like this.

Frankly, I bet over-oiling the filter is the culprit. You were really smart not to do this and that's why you have no problems.

[MNBoxster]

Originally Posted by Ghostrider 310

Just trying to help all other Boxster lovers. I have a K&N, I have had no problems, but if there is a proven propensity to ruin MAF's, then I want to remove it.

Hi,

You're in denial. The K&N is not a good piece of kit at all. It was first introduced as a long-life alternative to Paper Filters for RACING. Then, later, their Marketing shifted toward emphasising the Performance gains to capture the Street Car Market as well. To a Race Car engine, which is regularly stripped and rebuilt, longevity is measured in hours, not months and years. Consequently, none of the longterm ill-effects of using this filter were ever realized. Not true for Street Car applications.

With respect to enhanced performance, either the gains are questionable, unverified or Placebic, such as on the Boxster. Or, are explained away by the fact that the filter has much larger holes in it and so passes more air, but also more dirt. Adding more Intake Volume alone does little for performance, except the performance of the Aftermarket's Bottom Line. Most Dyno tests showing HP increases are on Cars which have been modified in other ways besides just the addition of a K&N Filter, such as Headers, Cams, remapping, new Plugs, Wires, Coils, etc. So, any increases can rarely be attributed solely to the K&N.

In some tests, such as this very scientific ISO 5011 Test - http://home.usadatanet.net/~jbplock/ISO5011/SPICER.htm , the K&N was PROVEN to pass 18 times more dirt than the best Paper Filter and was restricted in 1/3 the time, meaning that all performance gains, if any, are realized only in the first few thousand miles of Service. After this, they actually underperform their traditional, Paper counterparts.

Considering the Advertising gain of such scientific testing (an ISO 5011 Test will achieve the same results here, there, today, tomorrow), why hasn't K&N done such testing? The cost would be miniscule, especially if positive results yielded increased sales, they would recoup the cost in no time. But they haven't published any such testing... why not? Are they Marketing Idiots? Or are such tests not favorable to their product? Likewise with the evasive email they sent - hardly definitive. They don't even acknowledge the problem... but they qualify their denial beautifully.

OK, so we have a Filter passing 18 times more Dirt, so the obvious question becomes - where does all this Dirt go? Well, there is strong evidence that some contaminates and disables the MAF Sensor as most of the failures reported here are from K&N or similar Gauze Type Filter Users. Some passes through the Cylinder and Exhaust to lodge in the Cat(s) and lead to possible premature failure or reduced Flow (robbing Power). But, the majority of the Dirt passed through the Filter ends up in the Oil, shortening it's Service Life considerably (most people don't realize this or shorten their Oil Change Interval and so they allow the grit (and much of this Dirt is very Hard and Destructive Silicates - Sand) to flow through their engines for an intolerable period, shortening the engine's life). So, the trade-off seems to be some very modest gains (at best) while seriously compromising the Engine's Longevity and Ancillaries.

So far, it seems that the Detriments far outweigh the Benefits. Another consideration is that virtually all paper filters have a flow capacity which exceeds the flow demands of the engine, so is more really necessary or better? As an anology, next time you're filling up at a Pump priced at $2.60/gal., just give the Clerk $3.00/gal. instead...

Then, there's cost - several times what a paper filter costs. But add to this the added Oil and Oil Filter Costs due to shortened Service Intervals (not insignificant on a Boxster), and perhaps even the cost of a MAF Sensor or Cat(s). Suddenly, the Cost/Benefit ratio is becoming increasing skewed - and not in the K&Ns favor!

Of course, there is the fact that many can't leave well enough alone (Modoholics) and/or want to have Bragging Rights or follow the Herd. Well, the K&N performs marvelously in this regard... except for people in-the-know. To them, you will often look like someone who follows the Hype and really doesn't know what they're doing at all.

K&N and other Aftermarket Filters are popular and sell very well, but the Facts just do not favor their use...

Happy Motoring!... Jim'99

[TTschwing]

I have built and sold over 500 iintake systems (VTDA and TTDA) for the Audi/VW 1.8T engine based on K%N cone filters. This engine uses basically the same Motronic system as the Boxster (Maf based). I have had no problems with MAF fouling except when an owner, doing his first cleaning and re-oiling, gets a little too aggressive with the oil spray.
MAF's go bad. K&N's don't necessarily accelerate that problem.

[NickCats]

Thanks to all of you for such a great forum...

I was thinking of installing a K&N air filter in my Box and then I thought, "I wonder if anyone else has done this on the forum".

Rather than post another question, I used the great search function available and found this thread.

Needless to say, I will not be going with the K&N.

Also found a great link with step by step instructions for desnorkling :

EVO Chip for 2.5L

If you haven't already, familiarize yourself with the search function.

Great resource !

Nick

[TriGem2k]

And yet you still make a useless post.

hahah JUST KIDDING. I think some (like me at times) are just lazy and don't want to put in the work looking for information.

Good Job.

[NickCats]

TriGem2k,

You know, I was going to mention that :

"Rather than post another question, ( or make another useless post like this one ), I used the great search function available and found this thread."

Looks like you beat me to the punch...

( Wait, I just made ANOTHER useless post now, didn't I ? )

Thanks,

Nick

[Racer-x]

If you absolutely have to have an air filter, BMC tends to be better than K&N from what I know.

Your car is an air pump. Open up the exhaust first, then go to the intake. Not saying a drop-in filter is best, other options are out there waiting for you to search them out. Once you've freed up both ends, you get some extra performance as well as a great new sound.

Everyone stop talking about air filters now.

(lol)