K&N Addresses MAF - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Ghostrider 310 · 01-17-2006, 01:40 PM

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,

01-17-2006, 01:45 PM

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

RandallNeighbour · 01-17-2006, 01:46 PM

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

Ghostrider 310 · 01-17-2006, 01:55 PM

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

01-17-2006, 03:02 PM

Quote:

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 · 01-17-2006, 03:10 PM

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 · 01-17-2006, 04:07 PM

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.

Ghostrider 310 · 01-17-2006, 04:15 PM

Quote:

Originally Posted by 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.

Here's my take, my K&N is new so it is factory oiled. I have the K&N cleaner kit and oil from my 944 application. Instead of cleaning it, I will simply replace it. It will last far longer than a stock paper will so the cost of chucking it is the same or cheaper than replacing paper quicker. Replacement should prevent any over oiling issues.

deliriousga · 01-17-2006, 06:38 PM

There is zero HP gain from using a K&N, so why pay a fortune for it and take a chance on blowing the MAF? Go to the 928 forums on http://forums.rennlist.com and search for K&N. You'll see a ton of people who have experienced the problems.

Let's run a poll on MAF failure. I'll start one tonight so we can see what the numbers are.

Adam · 01-17-2006, 07:07 PM

I have had a BMC filter in my ride for 2 yrs with 0 problems. It's a cotton gauze filter like the K&N.

NiATE · 01-17-2006, 08:07 PM

One thing that has helped me personally is to blow compressed air across the filter when new or reoiled which, theoretically, removes the excess oil. So far so good. Some of the shops in my area recommend against them though. Just 2¢ more for the discussion.

MNBoxster · 01-17-2006, 08:17 PM

Quote:

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

Ghostrider 310 · 01-18-2006, 02:36 AM

MN,

I've heard this arguement posed by Porsche blogs everywhere, does experience count to you for anything? I have used these types of filters in a wide variety of vehicles over a 25 year period with no negative effects. As stated before, my father was a mechanic and car dealership owner for 40 years, never saw a problem related to the report you posted. If you do not like the product don't use it. There are many race teams using K&N and BMC, it seems doubtful they do it just for sponsor money, especially if what you posted is true. If you insist on judging the care given to the vehicles by people who do use them go ahead, I'm not asking you to drive or purchase my vehicle. As far as the blown MAF's go, I have read a plethora of other Boxster problems, RMS leaks, total engine failures, electical ghosts, if I internalized everthing I read I'd sell the Porsche and run...

MNBoxster · 01-18-2006, 05:52 AM

Quote:

Originally Posted by Ghostrider 310

MN,

I've heard this arguement posed by Porsche blogs everywhere, does experience count to you for anything? I have used these types of filters in a wide variety of vehicles over a 25 year period with no negative effects. As stated before, my father was a mechanic and car dealership owner for 40 years, never saw a problem related to the report you posted. If you do not like the product don't use it. There are many race teams using K&N and BMC, it seems doubtful they do it just for sponsor money, especially if what you posted is true. If you insist on judging the care given to the vehicles by people who do use them go ahead, I'm not asking you to drive or purchase my vehicle. As far as the blown MAF's go, I have read a plethora of other Boxster problems, RMS leaks, total engine failures, electical ghosts, if I internalized everthing I read I'd sell the Porsche and run...

Hi,

The issue is Long-term Ill-effects. These are progressive and won't blow-up your motor on any particular Sunday. Many issues, like the MAF Failures, are often attributed to something else, all the while ignoring the Root cause. For what? For 2-5 Horsepower? To gain 1-2MPH on the Top End? To be Cool? To save a Buck?

Again, Racing is NOT the issue here, quite the opposite. Because of the extreme maintenance a Racing Engine receives, most of the ill-effects of using a K&N Filter are either avoided (Race Engines do not go 15k mi. on an Oil Change), or are considered part of the Cost of doing business - Engines are consumables in the Racing Industry.

I Race and Maintain a Formula Vee, have for years. I do not use a K&N on it, rather, I use an ITC Foam Filter which is even less restrictive, but safer with respect to backfires, etc. I recognize that the tradeoff is protection, that this filter offers very little short of keeping the Rocks out. In my application, protection isn't the most important issue, but in someone's Street Car, it should hold a greater priority, or be prepared to pay. Every Race Part or Mod isn't practical for Street Use.

It's amazing to me the near fanatical loyalty K&N's Marketing has generated, for what at best is only a couple Horsepower. People wouldn't think of scooping handfuls of Sand into their Intakes, but there's only a quantitative difference between doing that and using a K&N Filter - the Test PROVES this to be true.

Are you saying that the Filter doesn't pass 18 Times more dirt than the best performing Filter? Are you saying that there is no possible negative effect in doing so?

Like it or not, believe it or not, the testing speaks for itself. It was conducted by the very Company which makes the Testing Machines and follows a strict and Repeatable protocol. And, they had NO AJENDA. They didn't single out the K&N Filter, or promote any particular Type or Brand, rather they tested a range of available Filters and Filter Types. The fact that K&N performed so poorly is just what the results show.

The great thing about America, is that as a Consumer, you are free to go in the Face of these Test results and continue to use the Filter if you wish. But, this forum discusses issues and trends in hopes of aiding fellow Owners get the best experience possible from their machines. I am not telling anyone which Filter to buy, but to use a K&N Filter in the face of such definitive testing seems, at least to me, a poor decision. Face it, the Test pretty much ends the arguement, unless as I said, one is in denial...

Happy Motoring!... Jim'99

Ghostrider 310 · 01-18-2006, 06:15 AM

I really don't want to compare dick size on this anymore, you do as you please. For the record, I do not think a properly maintained K&N or BMC allows more dirt in. If you clean these items without restoring the oil the proper "tact" is missing and then said item will pass more dirt. Please enlighten us and explain why racers use these filtration systems? For every report you post a counter report can be located, that's the internet way. I find it hard to believe that two separate companies have built loyal client bases out of knowingly wrecking engines.

MNBoxster · 01-18-2006, 07:01 AM

Quote:

Originally Posted by Ghostrider 310

I really don't want to compare dick size on this anymore, you do as you please. For the record, I do not think a properly maintained K&N or BMC allows more dirt in. If you clean these items without restoring the oil the proper "tact" is missing and then said item will pass more dirt. Please enlighten us and explain why racers use these filtration systems? For every report you post a counter report can be located, that's the internet way. I find it hard to believe that two separate companies have built loyal client bases out of wrecking engines.

Hi,

I cannot help what you Fail to Believe. But, whether you believe it or not, the Sky is Blue, the Sun Does rise in the East, and K&N and other Cotton Gauze Filters Do pass more Dirt. Forewarned is Forearmed...

Happy Motoring!... Jim'99

Ghostrider 310 · 01-18-2006, 07:13 AM

Quote:

Originally Posted by MNBoxster

Hi,

I cannot help what you Fail to Believe. But, whether you believe it or not, the Sky is Blue, the Sun Does rise in the East, and K&N and other Cotton Gauze Filters Do pass more Dirt. Forewarned is Forearmed...

Happy Motoring!... Jim'99

Don't worry Jim. you would be the last person I would contact in case of failure.

Happy Motoring was Esso's catch phrase, I know that because we started out as Esso dealers, exactly how many years you have with a wrench in hand? The sky is not always blue, few things in life are B&W....Now I'm done with you, feel free to iggy anything I post and I'll return the favor..

MNBoxster · 01-18-2006, 07:32 AM

Quote:

Originally Posted by Ghostrider 310

... exactly how many years you have with a wrench in hand? ...

Hi,

Going on 40 years now. No need to get Nasty just because the Facts don't weigh in your favor. I have not impuned you or your skills in the least. Try and remain Objective here...

Happy Motoring!... Jim'99

wvicary · 01-18-2006, 07:38 AM

I work in the automotive repair field and see many cars with failed mass air flow sensors from Audi,VW and Porsche. Not all of these used K&N filters and have seen the sensor failed on cars(both using OEM paper filters) with as little as 2000km with one customers 2000 model VW Golf that has well over 400,000 km on the original mass air flow sensor. The first generation of the sensor are rubbish and have a very high failure rate but K&N filters are rubbish for a street car but if you feel the need to use them after all it's your money. I have one customer who thinks they are the best thing since bottled beer and have solved every driveability problem in every car he's owned with the added benefit of increased gas mileage and HP. No matter what test I bring to his attention proving how crap K&N filters are he knows what he knows from using them over the years and that's the end of it.

MNBoxster..... well said, I agree 100% and am glad you are this forum.

Ghostrider 310 · 01-18-2006, 08:51 AM

Quote:

Originally Posted by MNBoxster

Hi,

Going on 40 years now. No need to get Nasty just because the Facts don't weigh in your favor. I have not impuned you or your skills in the least. Try and remain Objective here...

Happy Motoring!... Jim'99

Actually I think you have been backhandedly condescending, but guess what? you guys can have the whole forum, I'm D- U- N done posting here. Have a good day fellas.