space-junk

iTrader: (1)

hey guys, im not too sure if this is tech or not, but i had a question about K&N filters...

i have one on my truck (and i like it so dont tell me its a bad idea) and i havent cleaned it in a while... so i did the other day... before cleaning i was getting 19mpgs, but after doing it and running 2 tanks thru it ive only gotten a max of 16.8mpgs...

when i cleaned it, i did it a little differently than i normally do and i lightly sprayed it and let it sit for overnight to soak in... then the next morning i lightly oiled where i had missed...

usually i just spray the heck outta it and throw it in and drive off...



any ideas if it could be something else...

btw, i run mid grade gas in my truck every fill up...

abecedarian

you rinsed it after spraying the cleaner and letting it set overnight and before applying the oil?
how are your spark plugs looking?

you've read this, right: http://bobistheoilguy.com/index.php?...d=58&Itemid=66

space-junk

iTrader: (1)

no, no, no... i use the cleaner and get all the dirty oil out of it... spray it lightly with oil and then let it sit over night to soak in... then the areas that didnt get oil i lightly spray it again...

toyota4x4907

Some of the oil may have gotten sucked up into the intake and screwed with components....I dont know as in the 4 years I had a K&N filter in my truck I never oiled it. I sprayed it with compressed air a few times...but never oiled or "recharged".....I didn;t know I had a K&N (or even what K&N was) until like a two months ago.

abecedarian

interesting idea- excess oil contaminating / interfering with the afm vane.

raydouble

Yeppers, OEM paper for me always.

abecedarian

The US military used K&N filters on their helicopters in Kuwait, etc., not because they needed a filter, but rather because it was a fair trade-off between ultimate performance and making them last. No filter (typical mode of operation for a turbine engine)= short lifespan (bad for a helicopter), best filter= poor performance but long lifespan, K&N filter= compromise between best performance and lifespan.
I think that says enough on it's own.

toyota4x4907

Haha Thank you, thank you
Which helicopters? All of them? They must have had K&N specially make helicopter turbine filters....unless they used duct tape.....

djkeev

Hi,

Oxygen Sensors have a particular dislike for excess burned oil by products. I'd look real close at it/those (depending upon your model).

Dave

Shawsheen

TOo much oil is def. a bad thing on those. I used to roll with the VW's and it was very easy to foul out the mass air flow sensor, or something like that, with too much oil. You are better off under oiling as another poster eluded to IMHO.

Belize Off Road Team

Just like the instructions say on the cleaning kit from K&N...it is better to under oil than over oil. It is likely that you didn't leave the fresh oil soak in before dropping it back in and starting it.

Godzilla

I think this is a non-issue. It sounds like you did not over oil it. Letting it sit overnight before putting it in your truck is not going to change a thing, and based on your description I really do not see how any oil has damage your AFM, or anything for that matter. Try going a little more than 2 tanks in excess of your 2mpg drop and then start to troubleshoot.
After cleaning (not oiling) did you let the filter completely dry?

space-junk

iTrader: (1)

yes sir, i did...

i too think that the oil is a nonissue...

like i said, USUALLY i just oil the hell out of it and slap it in...
so the one time that i do it the right way i get screwed...

and i am dead religious about tracking my mileage EVERY fill-up, so noticing a 2mpg drop is huge for my truck...

Godzilla

Maybe its just letting in so much air now that your vehicle is adding more fuel to compensate.

surf4runner

i usually let mine sit ovenight too.
also gives a good idea if youve overoiled.
ive never fouled anything w/the oil.

usually takes 1-2 tanks before i see any improvement after cleaning.

arizonaguy

i think all of you dudes are being way too critical about mpg and a clean are filter, i dont think it matters how you cleaned it as long as it was dry before you sprayed the oil on it and as long as you sprayed it evenly, and only on one side, that being the side that is supposed to trap dirt and debris. I usually soak mine in a five gallon bucket for a half hour or so then spray off with a hose and let it dry in the sun all day. Usually i put it in the bucket first and then spray the hell out of it with foaming simple green then submerge it in with water then dry always dry dry dry before applying oil to one side only!!! it is also said to never use compressed air when drying a k&n filter because it ruins the filter element. Another thing the K&n filter cleaner is problably what a dude should use to clean the damn thing but i find simple green to be the key element when washing your >