A buddy at work has a 2000 F-150 4.6L SOHC. It has headers and a K&N FIPK. Sometimes when he lets off the throttle, the engine will moan at idle. As soon as he hits the gas, it stops.
He said his Ranger used to do the same thing.

Anyone ever experienced this?


Tom

 

I have the same prob with my FIPK on my '99 5.4L Expy. Mine has a breathy, whistling sound when I let off the gas, which goes away when idling. Kinda like "Vrooooommmm-whistle-silence" when I take off. I'm thinking about maybe putting the original intake back on - the K&N performance gains are created at 5,000RPMS - mine rarely bounces over 3,000, so I'm really not benefiting from the K&N. Plus, I hear that K&N's allow a lot of dirt through.

XXL

 

K&N Letting alot of dirt through? Sounds like you are an AMSOIL salesman.

K&N Filters have been used in the aviation industry when AMSOIL was still pooping yellow. Tolerances in aviation industry is very strict. If it works in that industry, it will work 100 times better in the automotive industry.

I have heard every sales pitch people have out there. Foam vs. Paper vs. K&N. If you think about it, Which is better? Only one really provides a better airflow, better filtering capibility, and is cheaper in the long run. Just try breathing through a sheet of paper or a sponge. It ain't going to happen.



Tom

 

>K&N Letting alot of dirt through? Sounds like you are an
>AMSOIL salesman.
>
>K&N Filters have been used in the aviation industry when
>AMSOIL was still pooping yellow. Tolerances in aviation
>industry is very strict. If it works in that industry, it
>will work 100 times better in the automotive industry.
>
>I have heard every sales pitch people have out there. Foam
>vs. Paper vs. K&N. If you think about it, Which is better?
>Only one really provides a better airflow, better filtering
>capibility, and is cheaper in the long run. Just try
>breathing through a sheet of paper or a sponge. It ain't
>going to happen.
>
>
>
>Tom

Amsoil didn't tell me that K&N's were bad, I've heard people around here mention that oil analysis shows larger silicon levels in vehicles with K&N filters. I'm also not an Amsoil dealer; I use Mobil1.

XXL

 

I have had more then one person make that statement that K&N filters dont filter well. Then someone would say "What filter do you think filters better?" then they would go off about AMSOIL. All I can say is that, My father has his oil tested, and he is an AMSOIL dealer (I am not selling anything and I only use it to keep peace in the house) and none of his vehicles have high silicon levels. Every vehicle he owns has a K&N. Our 1993 Aerostar, 1993 Thunderbird, and 1986 E-350 27' Coachman Motorhome.

He hasn't fallen for the "AMSOIL air filters are better then all others" scam yet. Hopefully he never will.


Tom

 

Here's how I see it: I'll send my oil for analysis. If it indicates taht the filter isn't filtering well, then it's gone. Otherwise, I don't see any reason to toss it, other than the funky whistling noise.

XXL

 

>A buddy at work has a 2000 F-150 4.6L SOHC. It has headers
>and a K&N FIPK. Sometimes when he lets off the throttle, the
>engine will moan at idle. As soon as he hits the gas, it
>stops.
>He said his Ranger used to do the same thing.
>
>Anyone ever experienced this?
>
>
>Tom

I have had the same thing in my 97 Ford Expedition. I have metioned it to the dealers numerous times, but they just don't hear it. Good luck with yours. Have a great day.

 

[updated:LAST EDITED ON 16-Dec-02 AT 11:36 AM (EST)]When I installed my Volant FIPK the supplied hoses at the throttle body didn't fit (I blame this on a Volant design issue but that's another topic for another forum). In order to make it work I had to remove a plastic 2" square box looking thing that was inline on one of those hoses and then get a different hose from the parts store and rig it up. The box is empty and I figured that it couldn't do much since it had no working parts etc. I found that with that box missing the truck would make a moaning sound only at idle, especially when the truck is cold and not all the time. From another Ford truck site I found that this box is an example of Ford reverse engineering and is only there to prevent that moaning sound which comes from air flowing through the hose. There's no adverse effects on performance with it gone but the sound is kind of annoying.
Hope this info helps you out.