You regulars will maybe remember my mileage report from last month. I was surprised that my K&N filter didn't provide any measurable MPG increase given that the truck "felt" more open during WOT runs. I knew it was time to pull and clean the filter, so I started thinking of going back to the stock paper filter just because of the increased filtering capacity.

Then I started wondering about the heavy pinging I got sometimes during high RPM runs while pulling my trailer. This was a new phenomenon this year and I realized it only started happening since I put the new K&N in. The pinging was constant and pretty bad once I got up near 4,000rpm. The computer didn't do a very good job of controlling it, so I always had to back off the throttle to find the sweet spot. I decided to pull the K&N and put a stock filter back in. Last weekend I made a run up the mountains with the trailer and it included a couple of high-RPM sprints. Not a single pinging issue and the truck felt better pulling the heavy load (which makes sense…I was staying in the throttle and all 10 cylinders were firing on schedule).

So…the K&N went into the garbage. Not sure why the computer couldn't adjust to the increased airflow, but it didn't...

 

I also removed my K&N but for a different reason. It seemed to make my mass air sensor too dirty. I always liked a back road trail which can be really dusty. I never saw any difference in gas milage either way.

 

The inside of my intake also had a very thin layer of dust on it. But I know the service idiots left the intake assembly unlatched when they were finished working on my truck about a year ago (a few months before I got the K&N). I didn't discover it until I went to install the K&N, so I'm not sure where the dust came from.

I can tell you everything is clean now!

 

Where the motors reportedly run at or near stoich condition, could the increased air flow cause a lean condition?

 

That is what I think was happening. A lean condition will lead to pinging. I guess the computer couldn't get enough fuel into the cylinder to get the right ratio for the increased air.

 

My '05' 5.4 I tried the K&N and removed it after awhile more hassle than it was worth. Good old tried and true paper for now on.

 

i have a K&N in mine now and i think i still have the stock paper so you guys think i should switch back??

 

Personal preference, some guys use them and never seem to have problems or mind using them.

 

personaly i just prefer the OEM level quality paper disposable filters.

use till dirty, then replace.

i've always found the K&N stuff to be overrated in real world scenarios.

 

I agree with Scraprat's comment…some guys use them and don't have any problems. Some even claim to get MPG increases. I've tried full intake kits and drop-in filters on multiple gas powered vehicles now and have had problems will all of them. I'm done wasting my money on any kind of intake "enhancement".

I think the only obvious reason to switch back is if you're in a dusty environment. While everyone's results may vary, I think everyone agrees/knows the increased air flow comes at the cost of filtering.

 

I've always had great luck with K&N drop in filters. Never used a cold air intake before and I'm not really looking to get one. But the K&N is a lot of maintenance, which isn't something a lot of people don't wanna do and I don't blame them. It's a pain when u do it every oil change like i do

 

I use the K&N filters unless there are frequent dusty conditions. More air flow=more particle flow. More particle flow decreases engine life. Just to save a couple bucks on air filters? Just use the stocker IMO.

 

I need to tear that greasy turd out of mine. IT has been doing nothing but getting the maf dirty and the truck run like crap

 

You don't have to clean it that often, I have a 110K on mine filter and I still some of original can of oil spay lift. I just cleaned mine and it had about 20 to 25K on it since the last time I cleaned it, that's also the same can I used on my work V10 truck that I sold with 100K on it, that truck was always in gravel roads and dusty conditions. I have never had any problems with any of my MSF sensors on any of my trucks that I have run a K&N on, I also have never had any dirt in any of my air intake after the filter.

Denny

 

KN filters require very little cleaning. A bit of dirt enhances their filtering ability.