I just bought a used Injen and noticed the inside of the pipe to have a layer of freaking sand, not powdery dusty stuff but engine killing miniature rocks like on 120 grit sandpaper.

Is this commom knowledge that the K&N type filters on these things dont filter out crap but its ok because the claimed increase hp?

Is this filter defective? Is there an alternative filter that can be used, better suited for direct exposure to high speed granule impacts (rockchips on a filter?) How about a foam filter, like a UNI or Amsoil?

Please help me, great ones.

 

My past CAI was the same way, sandy substance on the inside. I ended up washing it (like dishes) and waited for it to dry. Then the install.

 

Washed it?!?!

If I had an air filter or CAI that was letting any sand or grit past the filter I would not just wash it and replace it. (not flaming you, I am just sating....)

For each piece of grit that happened to stick to the sinside of the tube there are probably 1000 more that made it in to the engine. This kind of grit can kill an engine pretty damn quick.

If it is a K&N style oiled-gauze filter it should be able to do better than this. At most you should get some very fine (like baby powder) oily-dust past it. I have had a K&N on several vehicles and I never found grit like that.

If the filter was cleaned and oiled properly (ie let it dry before oiling it) then you probably have an air leak that is letting air bypass the filter. To find this type of air leak you can use a section of small tubing. Put one end in your ear and use the other end to listen for the leak.

If you can't stop the grit from getting in I would recommend going back to stock or buying a different kit. This type of grit is no joke when it gets in the engine.

Just my $0.02 of course.

 

My Injen was like that too. Just clean it out.

Victor

 

What ever you do, do not clean your filter, it is known that k&n's will pass dirt until the filter becomes dirty, I mean really dirty. Once they become dirty they catch more dirty, but still flow well. I found this out on my own with 4x4's and atv's that I have owned. I would only clean mine after they became saturated with mud. When running the truck on the road (like thru the winter) I would sometimes just re-oil the filter if needed. As long as you don't soak the filter, I had no issues with the MAF. Even if it was dirty (maf) i believe it can be clean with electrical contact cleaner.

 

Maybe I misinterpreted the post... when I FIRST bought one for my Civic (o' so many years ago...) the tubing had a sandy like material on the inside of which I washed. I never had anything noticeable pass the air filter itself.

And no, I never washed the air filter (except with the approved package by K&N), I was referring to the anodized tubing that connects the filter to the throttle body. That had some weird sandy material, but it was taken care of before install.