Oiling K&N air filters
 

What are the engine symptoms if you over oil your K&N air filter?

A little more info is needed...

What year car.... stock or modified engine?

I doubt there would be any . . .

I agree.

Unless you really just went frikkin' nuts with oil on the filter it really shouldn't cause any major problems but maybe a bit of smoking once it gets into the intake andgets burned off.


His garage lists an 88 Carrera so we can probably believe that he has a cones style filter.

88 targa but with a stock air box. Thanks for the input. I wasn't sure if the air filter was the culprit as the car was idling a little rough and on take off seemed to veer toward stalling unless I gave it a little more throttle. The car is one tank full out of winter storage where I used stabil. Did the plugs and valves just before putting it away. Put in a can of seafoam today. Maybe that will help.

on a car with an air flow meter, excess filter oil can mess it up (which is one reason many people don't like k&n). but I don't think our old cars have one.

The contamination of the MAF by K&N filter oil is a wives tail used by dealers to get out of paying for failed sensors.

If anyone ever has a MAF sensor that the mechanic says has failed because of the oil from a K&N they should immediately call K&N. They will help you with the claim. They actually send out the sensors to have the "fouling oil" checked with a mass spectrometer. They have never seen a failed sensor from filter oil. The oil always turns out to be oil that has leaked out of the failed sensor itself.

But it is true that if to much oil is applied to the filter, which can happen, that this oil can make it to the maf thus causing issues in regards to proper fueling.

On many Mustangs (sorry), the MAF has a very thin sensor wire that runs right across the air flow. It can be fouled (and give bad readings) if you really over oil a K&N. BTW, there is no other source for oil on this setup.

For those who do use a K&N, the aerosol filter oil is much easier to use than the drip kind and much harder to over oil with. Although I am sure some people could still do it.:D

one way to avoid this is to use the sticky spray on oil that dirt bikers use. Its a little tougher to clean, but it is much easier to oil the filter and not over oil it. on SC's, 3.2's over oiling would just bring oil into the intake, maybe a bit of smoke from combustion, but you;'d have to go nuts with the oil.

I don't oil my K&N but then I don't live in a dusty, dirty area - too much rain for that. Besides the oil is changed every 3K, so not really worried about it. Just clean the K&N with every oil change.

And over oiling my K&N on my old 20V turbo Audi Quattro did foul the MAF which was rather pricey to replace. After replacement and going back to a stock oil filter the car ran fine.

MAF fouling can be cleaned off with spray product. Sensor will not get destroyed from over oiling.

Want to know how good your filter/housing is? Simple test of smearing some wheel bearing grease on surface downstream from filter will either remain clean or catch dust getting by.

K&Ns need a pre-filter sock for dusty areas IMO. But test for yourself and see.

Is there any advantage to a K&N filter over a clean OEM filter? Any advantage to a cone filter vs a K&N that firts in the stock air box? I understand that the airbox and filter is not the choke pioint for a stock 3.2 engine, true? What is the most restrictive point then? The ads claim and increase in horsepower w/ a less restrictive filter.

If the rough idling just started after you oiled your K&N filter I'm wondering if you pulled one of the rubber lines lose? I'm guessing that some where in all those hoses behind the filter box is a vacuum hose?

darcher - my understanding is that there is no advantage at all

some old threads if you want to search

or... consider that P AG is very big on "green" issues and has been for some decades - from at least the early '80s their policy was to not raise the hp on a motor unless they could achieve better fuel economy at the same time (according to Aichele, IIRC)

so, you might expect them to use an oiled, "repairable" filter instead of adding to landfill space (a huge issue in Germany) with a disposable paper filter - but they didn't