Thread: Are K&N air filters safe ?

NO! NO ! NO! Do not do it.

I had one on for about 4 years on my 3.9 Rangie.
Took it off because I found dust in the MAF sensor.
Also coated the MAF with oil. I cleaned the MAF sensor with no residue electronic cleaner when I put a snorkel on recently(and took off the K&N), and noticed my fuel economy went bad. Took it for a dyno tune soon after as I had also put modified heads on.
The car was running full rich(11:1). Traced back to soon after I put the K&N on and it started idling badly. When my mechanic checked the CO it was down to 0.9 so he richened it by increasing the MAF resistance. MAF resistance was 260 OHMS instead of 140?.
The Stepper motor hides a lot of the problerm as it compensates for the bad MAF sensor signal. Also I had increased the base/kerb idle to compensate , as it used to stall on sharp letting off throttle. Found after cleaning of the throttle blade that the base idle had increased also.
So now it runs GReaaaat.
K&Ns are great for carby cars and flappers but not for those with a MAF sensor. K&N argue this but that is my personal experience.
Regards Philip A

We had an reusable filter (sock) on the quad used to be okay, not great but better than nothing, at keeping dust and splashed water out of the motor. So brand name aside, oil soaked filters work okay depending on their application but agree with Philip

As an option on the Disco I think the oil bath style would work better. Was common once for machinery to have them and most series rovers had them too. You might be able to ditch the factory filter chamber/box and install the oilbath in it's place and hook up to the original engine inlet pipe.The filtration will be four times what that oily sock will do as there's cartridges inside besides the oil bath in the base.

Either that or go to 'norkel and donaldson precleaner which is what I have on my series. Works unbelievably well, so much the main paper air filter has been checked regularly but cleaned once in three years. Have to be happy about that. [img]style_emoticons/<#EMO_DIR#>/biggrin.gif[/img]


Both mods will require a fiddle of the management system to correct any out of line values but at least you'll be safer when it comes to keeping dust out of the motor. [img]style_emoticons/<#EMO_DIR#>/biggrin.gif[/img]

I ran Finer Filters on twin webbers for years racing off road,,
the trick is maintenance,,
Oiled foam needs to be maintained regularly, and I'm not talking every 5000 klms or so.
In fact the amount of work required to keep the filters working properly (on a road/4wd- car) is too much to contemplate.

[not MY engine bay---:wink: ]


Buy the Donaldson.
and a steel cap boot.

I agree with Pedro, i use K&N on my Kawasaki ZX-12 bike which is outrageously modified now and have zero problems, and it gets damn dusty out here [img]style_emoticons/<#EMO_DIR#>/laugh.gif[/img] The trick is maintenance, keep 'em cleaned and oiled. If you're not up for the extra maintenace / not chasing every last HP then stick with paper or an oil bath. Just mu 0.02 worth
Bill

Yep i'm with Pedro lot more work involved with oiled reusables but are much more gooderah in the long run," for racing anyway" oiled filters trap finer particals than paper causing less engine ware.

K&N are a large American company and the Ford Explorer too, Ford recomend K&N filters for the Explorer as a better filter replacement for the paper filter and the Explorer has a very sencitive MAF senscor, our fuel economy improved after installing the K&N filter.

Will not stop water though [img]style_emoticons/<#EMO_DIR#>/sad.gif[/img]

NOT WORTH THE HASSEL.

MIchael.

Originally posted by Redback
K&N are a large American company

No they are not!!!

They are a UK company - based near my home town in Warrington Cheshire!!!

They do however sell mainly to the US / European countries.

LRH

I can assure you that K&N , Uni filters etc are a certain way to contaminate a Hot wire airflow meter, happens all the time. We use 3 big ones them on the race car but it doesn't have an airflow meter, I've set the injection up purely on throttle postion.