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Actually the dirt and debris with the K&N filter shows up as silicon in the oil analysis. I know as I tried their filter in my other vehicle. I stopped using it due to the sharp rise in silicon.
.. "which investigated the high failure rates of modern MAF sensors. Several factors where involved which revealed what many have suspected all along.
Higher air flow capability with the K&N is the result of larger pores in the filter media to offset the smaller total area when compared to any OEM filter. Oil is used to help trap the dirt when it comes in contact with the filter media. One of the aspects of this design allows what is referred to as "Tracking" where certain regions of the filter media as a result of internal air box flow patterns directs particles to specific regions of the filter more than others. What occurs next is those regions lose the oil saturation to the increased dirt loading allowing particles in the 90 micron range to pass through the media since there is no longer any more residual oil in the local pores.
Oil migration. Oil migration occurs when the motor is in warm climates and/or operating at high engine speeds where the volume of air passing accross the filter carries small amounts of oil into the air stream post filter which is now entering the motor.
Particles less than 90 microns... Pull a hair out of your head and push it through the filter media, if it passes through you have a filter with pores GREATER than 100 Microns in size! This is the primary issue with MAF sensors. MAF sensors rely on filtration quality that captures 95% of all particles greater in size than 15 microns. Ideally 10 micron capability would result in longer life but now the physical size of the filter is increased to offset the fine fitlering capability when using conventional or synthetic fibers in an "Un-Oiled" air filter.
MAF air flow sensor design. MAF sensors use micrscopic heating elements placed on a circuit board. The heating element provides a constant rise in temperature to provide a known condition for the ECU to calculate air flow. On the leading edge of the MAF sensor is a temperature sensor which measures the temperature of the air passing over the leading edge, this temperature returns a value to the ECU. As the air passes over the heated portion of the MAF sensor heat is transmitted to the air stream thus heating it. As the air passes accross the back portion of the sensor a second temperature reading is taken. Higher flow rates result in lower temperature rise, lower flow rates result in higher temperature rises.
Another aspect of the MAF sensor is static build up on the leading edge of the sensor element. This static charge causes small particles of dirt and debris to adhere to the elements leading edge distorting the laminar flow characteristics of the sensor throwing off the temeperature readings take accross the elements surface. Over time rotors form accross the back side of the build up depositing oil, dirt and anything else that is in the slip stream directly onto the heating elements surface. What happens next is that the oil/dirt or any combination of the two insulates the heating element causing it to overheat and short out. The result is a complete loss of data to the ECU causing it to revert to default values stored as a limp home function.
The precursor to the failure is often a reduction in peformance as a result of inaccurate thermal readings accross the sensor plate. As the dirt accumulates power typically drops off until the heating element fails.
OEM air filters believe it or not out perform K&N in all aspects. This is easily done by using filter media which has much smaller pore size (5 microns on "average") this allows typical filtration to hit the 10-15 micron range with the 95% effective range. However the fine filtration capabily results in more restriction, the restriction is offset by increasing the depth and number of the pleats the media uses. The biggest advantage to this is that the OEM filters are able to go 50,000-100,000 miles between changes WITHOUT resulting in any increases of restriction or worse yet ALLOWING MORE DIRT TO GET IN THE MOTOR! OEM filters REGARDLESS of miles or time in use perform as well or BETTER the more they are used again up until the reach the maximum restriction point (15" or 25" WC).
Most OEM air filters have anywhere between 1-4" water colum of restriction when new. A fitler is considered to be "Loaded" when restriction reaches 15" WC on naturally aspirated motors and 25"WC on turbo or supercharged vehicles. Regardless of how dirty the filter may look provided restriction does not exceed the above numbers the filter is providing 95% efficiency at removing all particles greater than 10-15 microns.
Bottom line is that using any type of high flow filter that does not meet the 95% filtering capability at 15 microns is asking for trouble.
Call K&N and ask them what their filtering efficiency is at 15 microns and if they will warranty the MAF if it becomes contaminated and burns out... I will save you the time, they will laugh at you and not do a thing."
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Also, K+N air filter dirt and debris won't show up in an oil test (that's absurd, just like this thread) but in the scratches on your coated cylinder walls. "NO THANKS"
Attached is my oil analysis from my 2003 Toyota 4Runner which had over 100,000 miles on the K&N air filter and around 213,000 miles on the engine at the time this was done. The car has well over 222,000 miles on the original motor at this point as I speak. I never had any issues with the MAF sensors on any of the three cars which had a K&N air filter. I am getting a new filter for it because its too dirty. I will do my ML350 oil analysis next. Any of you care to post your results?
Useless report. As you do not note or state how many miles that oil as seen before you sent the sample in. For all we know that's oil has only seen 500 miles.
No one cares about the UOA from your other car. Besides, a UOA only tells you how much life the oil has left in it. It is no more relevant to the topic at hand than the expiry date on the milk carton in my fridge. Why are you still trolling?
Well, I found out something last night about K&N that was very disappointing. They are owned by Goldman Sachs...yes that is right they are owned by the devil himself. I hate Goldman Sachs and anyone with an MBA knows why and know how evil they really are, documentaries have been made about them. It kinda makes me not wanna buy any of their products anymore. I know AEM had this oval tapered dry filter that didn't use any oil, but those were also made by K&N I believe.
So the question of whether to go oem or K&N has been an age old debate and I can't seem to find more independent testing to see just how well they perform when compared to oem. We know that the more air flow the more dirt it will bring in, but exactly how much dirt is too much and how much harm are you doing to your car when you use K&N filter. The piston rings are gonna be the first to go if there is too much dirt in your engine. Having fuel in the oil is another indication. My oil analysis didn't look too alarming for the 4Runner even after 100,000 miles on those K&N filters. I might just put my oem filters back on and do another oil analysis just to compare the two results (OEM vs K&N)
@d_787b The reality is AEM and K&N filters are just "feel good" items. As you have discovered there is very little independent testing on the merits or issues using them. The reality is you are driving a non-turbo vehicle, normally aspirated engine, so increasing/enhancing air flow with AEM or K&N filter will not amount to much if any performance gain. It's doubtful you will notice or even feel any gain, except maybe your butt dyno !!!! Also if you do go down the path of AEM, you should get the engine tuned to make use of the enhanced air flow.
For you own interest you should research Brabus, since they do all the performance enhancement for MB to see if and what they have done for your engine. Maybe you can copy/follow what they have done.
AEM DRYFLOW delivers "filtration efficiency of 99.52% cumulative filtration efficiency
and filters out particles as small as ONE MICRON in ISO 5011:2000 independent performance filtration
testing using A-2 FINE TEST DUST."
Meaningless and useless report. I doubt anyone here cares enough to read the report. The reality as I stated before, you are driving an N/A engine and not a turbo engine. Increasing airflow does very little for performance of your vehicle. Combined with the fact that you are sucking in hot engine compartment air instead of sucking in air from the front grill!!!! And you want to do this just so you can save 5-10 minutes of time every 3-4 years is why everyone here is saying "Go ahead do the mod, but don't expect any performance gain".
Every person I have had discussions with on other car forums about doing similar mods, only brag about "performance gain". But they never actually put the car on dyno and post their pre mod and post mod results on the respective forum. In fact these individuals end up never posting again on those forums.
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren
Slideshow: A one-of-one U.S.-spec Mercedes-Benz SLR McLaren Roadster became even rarer after a factory-backed transformation at McLaren's headquarters.
!!!! Also if you do go down the path of AEM, you should get the engine tuned to make use of the enhanced air flow.
