Are cold air intakes and K&N filters a big scam?

I put one on a 1995 Lincoln Town Car a while back and it sure sounded better breathing, felt faster at wide open throttle, but I noticed a big drop in gas mileage. Maybe from 17.3 or so average to 16. I suppose if the MAF senses more air it will dump in more fuel. But under normal driving conditions the cold air intake isn't gonna suck in much more air will it?

I'm thinking about putting one on a 1997 Sebring 2.5 V6. It's a really high strung low torque motor so I thought it might sound better and pick up maybe 8-10hp with a cold air intake. I'm just starting to think they may be a big marketing scam along with K&N filters being so great. I mean the big car corporations put endless efforts into research and development. I was always under the impression that K&N filters just use materials which would be too expensive to mass produce for production cars but that even seems dumb when I think about it.

But then again how can K&N and all the cold air intake companies go around claiming you get 12 more HP and 2 more mpg if it wasn't true? If people expect that they're gonna see if they get an increase in mileage. If they didn't then K&N would be called out on it.

What do you think and please back up your answer?

10 Answers

  • 8 years ago
    Favorite Answer

    K&N replacement air filters and performance intake systems offer better engine performance as well as outstanding engine protection. One thing to note is that the word airflow is used as a simplified term to explain a more complicated physical process. The more precise description is restriction: K&N air filters create less restriction which helps an engine run better. An engine will only use the air it needs and K&N air filters do not result in an engine using more air than necessary. Rather, they result in the engine experiencing less restriction. The terms airflow and restriction are inversely related. K&N air filters provide either less restriction at a fixed airflow rate; or more airflow at a fixed level of restriction. In neither case is more air being used than necessary. So the use of a K&N air filter does not actually push more air through an intake and will not cause problems with the MAF sensor. This decrease in restriction can benefit the vehicle in terms of its HP and torque. All of K&N's intake systems are dyno-tested and guaranteed to increase your vehicle's horsepower. Instead of making a general claim, K&N publishes actual intake system horsepower increases for many part numbers and vehicles.

    With regards to fuel economy, K&N does not make any claims regarding mileage. There is a relationship between air filter restriction and mileage. The theory behind this is simple, the harder an engine has to work to suck air through the intake tubes and air filter, the more gas gets wasted in the process. Many K&N users report an increase in their fuel economy after beginning to use the air filters, as noted on K&N's testimonial webpage. However, these experiences do not mean you will also experience a change in your mileage. While it is understandable why it is theoretically possible for a consumer to experience a mileage increase after installing a K&N air filter or intake system, K&N does not go so far as to make a general claim that our air filters and intake systems will provide an increase in mileage.

    It is virtually impossible to make sweeping and general claims about mileage. Even the EPA fuel rating numbers for new cars are often not representative of the mileage you actually experience. There are many variables that affect mileage such as: tire inflation, the type of fuel, weather, elevation, the speed at which you drive, the gear in which you drive, the speed with which you accelerate, engine maintenance, excessive idling, cruise control, the grade of motor oil you use, and of course, the condition of your air filter. In short, mileage is complicated. K&N filters are less restrictive than disposable paper or synthetic air filters and K&N Intake Systems are less restrictive than the factory installed air path. So K&N filter technology could be an important tool, when combined with other elements, to help keep mileage as high as possible.

    Oh yeah, there's one more limitation imposed by science. If you take advantage of added power by driving more aggressively, you will reduce mileage. You cannot have your cake and eat it too.

    -Vincent Pistonetti

    K&N Product Specialist

  • ?
    Lv 7
    8 years ago

    All modern cars already have cold air intakes. The main difference is the stock intakes include preheat to warm up the engine quickly - aftermarket intakes deliver poorer fuel economy, especially in winter, because every warm-up takes longer. The fuel economy improvement is impossible - I canna change the laws of physics - unless it is on a carburetor.

    Aftermarket cold air intakes are throwbacks to the 1960s and 1970s, when most cars had intakes that sucked hot air in from above the engine and had carburetors that cared a lot about intake restriction. With carburetors restrictive filters acted like chokes, making the mixture run rich. Modern electronic fuel injected engines don't care about intake restriction at all except at full throttle and near maximum power, where low restriction filters can increase power up to 5%... usually more like 3%. It seems like a lot of work for a change you can't even feel for the few seconds a month it would actually exist.

    There are also the dark sides of aftermarket filters. Our New Guy at work had a Scion that he put a K&N filter on. He never was able to get the check engine light to stay off, the result of turbulence around the MAF sensor. One day last July he drove through water that was deeper than he thought and the aftermarket intake slurped up water, hydro-locking his engine and bending a rod. He got the water out and drove it, ignoring the rod knock until the rod broke and punched a hole in the crankcase. He sold it as a project car.

    Source(s): 35 years maintaining my own cars
  • Pete M
    Lv 7
    8 years ago

    While cold air intakes CAN improve HP, they won't give you more power and better mileage.

    That's just not possible.

    It's also necessary to reprogram the computers on today's fuel injected cars to take advantage of what little those intakes really have to offer.

    It was different before cars became computerized and cold air intakes actually could be bolted on and result in a decent power gain.

    In my opinion, due to my research (see links below) I believe that they are scams and really don't do what they say they will do.

    I can't explain how companies do get away with advertising the impressive gains, but they do and they get away with it as well.

    Carefully read through the first link below and you'll see what I'm referring to:

  • Ok guys the colder the air the better the fuel burn more HP= more power K&N air filters advertise they flow 20% more air the more air in the more HP THE ENGINE WILL PRODUCE

    Source(s): 30 plus years mechanic not tech!
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  • 8 years ago

    @ Pete how can you say 'It Will give you more HP, but no more power?? ahh if you have more HP doesnt power increase??......anyway..the reason I put a K&N filter in my vehicle...was simple economics...I didnt have to spring for $50 for a new air filter every 2 oil changes or so..K&N was 70 bucks and lifetime ..IM saving on air filter charges...not mileage..

  • always keep in mind that when you have more power, you are burning more gas. it is a simple bit of science. the air filters that you mentioned so what they were designed to do. the cold air intake does exactly what it says. it is not an increase of volume but the density of the incoming air is what changes. the more dense the air coming in, the more fuel is added to match it and more power is developed. looking at your figures, you are getting a mild boost in the output for a smaller ding in the fuel economy. it works out.

  • 8 years ago

    I think they are a bit too expensive , I know that they make the origional fitting air filters that you just drop inn and go on ur Mary way . If it's anything else than a drop in filter , it's a waste of money . I red blogs about people having to put their sensors into a tube and just wrecked air and fuel mixture ! If you want better fuel mileage replace your fuel filter instead !!!!!

  • Anonymous
    6 years ago

    I have been a professional auto mechanic for 30+ years. First off the answer to your question is "I don't know" What I can say is this. On almost every modern car I have seen that has had a "cold air intake" installed, the result is an INCREASE in the average intake air temperature. This can be measured easily using any scanner. I make it a habit of noticing what the intake air temp is on most every car i drive. On an average stock intake system it is between 8 and 10 degrees F above ambient air temp. On the average car with a "cold air intake" system installed, the intake air temp (IAT) is 20-30 degrees above ambient. Of course I have seen exceptions in both cases but this is the average.

    Next, my experience is that many if not most people who install reusable filters (K&N or otherwise)pretty much install them then forget about them or they over oil them and the come in literally loaded with oily dust and mud which would defeat any benefits the high flow filter originally had.

    They do make the engine sound louder and many who have installed them experience a measurable decrease in fuel economy and I believe it is because their foot becomes heavier because they like hearing that roar in the intake.

    I have seen bits of oil and fiber from the filter contaminate air flow sensors, leading to check engine lights and running problems.

    I think on balance if you want one, get one, go out and buy the soap and the oil for it and take care of it as often or more often than a conventional filter. Most of the time the benefits and or drawbacks are minimal.

  • 5 years ago

    1. It might rely upon the quantity of miles driven and the external air stipulations the place your automobile has been pushed with out the filter. Metropolis air at the same time using is dangerous. Smooth country highway miles are better. #2. If their is any harm in any respect to the rings and cylinder partitions the harm is reversable with new rings and a very gentle *Sunnen Hone job if the vehicle hasen't had a variety of miles. If the motor has over one hundred,000 miles it's going to ought to be stripped down, cleaned and re-bored and honed to the next closest piston and ring size. #three. A cylinder compression and cylinder leak-down experiment would tell you in seconds the conclude and seal of the piston rings to cylinder-walls. Do that scan first earlier than worrying about spending some huge cash.

  • 7 years ago

    Not a scam at all, especially if you plan to keep your car for awhile. It's much more cost effective than just buying a "throw away" filter. I've had a K&N installed in my 2003 Camry for almost 200k, no regrets!

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