Anonymous asked in Cars & TransportationMaintenance & Repairs · 1 decade ago

Has anyone had problems caused by a K&N filter? Wondering about mass airflow sensors.?

I’ve heard stories about people having warranties voided for using these things because the dealer claims that an over oiled K&N filter will cause mass airflow sensors to fail prematurely.


OK I know a mass airflow sensor can be damaged by oil, this can also be caused by excess blowby too.

How did the dealer know it was from the filter and not some other cause?

11 Answers

  • 1 decade ago
    Best Answer

    First, it helps to know how a mass airflow sensor works.

    Basically, it heats an element and determines how much current it takes to heat the element 100deg F above ambient air temp. (measured with integral air temp sensor) The current demand needed to keep the element hot is directly porportional to the sensor's output to the computer.

    If you get oil on the heated element, you insulate it from the air......preventing an accurate reading. Then, the oil cokes carbon onto the sensor from the heat.......which insulates it even further. The MAF sensor will turn up the heat even the point of failure, even.

    And that's why oiled air filters are not factory equipment. (and you thought you were smarter than the engineers, lol)

    Keep it dry.....and you should be ok. Repeatedly cleaning a MAF sensor to cover up an error in judgment is simply hard-headed.

    Source(s): certified master mechanic
  • Anonymous
    5 years ago

    mass can be fouled by over oiling you k@n filter if you clean the filter properly and dry it spray oil until you have a light pink on the filter I seen some filters I pulled out of a case that had oil puddles in the lower case to much filter oil will cause big problems , at the same time do not use choke spray to clean mass it will leave a film you can buy mass cleaner but pretty costly but bang for the buck rubbing alcohol put in a container and soak the mass that takes all residue off the mass for a lot of you some mass problems will not set a code so be smart in testing problems good luck to all>>>>

  • 3 years ago

    K&n Air Filter Problems

  • Anonymous
    1 decade ago

    MAS can be damaged by oil from the filter getting on the wires

    and its NOT warranty when it happens

    the biggest problem I see with K&N is that

    no one ever cleans the filter

    its not real hard to do but you have to did it and when the K&N sticker says good for 100k that is not true in all areas , dust is dust and when the filter is dirty it needs to be cleaned or replaced so use the stock filters and replace them when required by the owners manual

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  • 1 decade ago

    not totally true but the oil can foul up the MAF. you can just spray some carb cleaner on the wire inside and it usually helps the situation but in all reality any after market parts can make a dealer want to void your warranty

  • Anonymous
    1 decade ago

    That is correct...too much oil will screw up the sensor, and a warranty claim can be denied. You shouldn't even install aftermarket parts like that on a car under factory warranty.

  • 1 decade ago

    I have used air/aide also k&n after cleaning i don't oil every time as the oil is not washed out. Just clean more often. I have seen ones that they have oiled so it looks like a KFC wouldn't hardly run.Yea to much oil will fowl the mass air sensor.But the oil will only affect the warrenty on the senser.not all the warrenty on the car or truck.

  • Lucy
    Lv 4
    4 years ago

    This is true. if theres alot of oil on the filter it could. i have one on my camaro but never had nay problems. people mostly get problems after cleaning it with the oil because they use to much oil to clean it

  • 1 decade ago

    yes it can happen,it happens to about 1 out of ten vehicles,you can buy a cleaner to spray on the maf to clean it with at any parts stores now days,but the excess oil can cause problems,it doesn't happen to all of them though.good luck with it.

    Source(s): been a certified mechanic for 37 yrs.
  • 1 decade ago

    had a ford ranger 94 and it did it to me to k&n filter

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