[N8N]

Hi all,

Not sure how this happened, but today I finally realized that I've never physically seen the air filter element on my car. Well, it was apparently replaced at least once as it was date coded 2011 and looks fairly clean. So that's good. I don't feel bad about missing it now (I'm usually pretty anal retentive about maintenance, to the point that I've already changed literally every fluid in the car since I've purchased it.)

Question is this - looks like it is a straight shot from the air intakes to the filter box, and again from there to the turbo intake plumbing. I swear I've seen mention of people removing a secondary filter/silencer before, but I didn't see anything that looked like that. Realoem diagram was no help. Am I missing something, or is this silencer that I'm remembering reading about something that's only on other engines and the N54 doesn't have it?

[deadmn1337]

I'm pretty sure what you saw or are remembering is for the N52 not the N54 engine.

[E90Company]

There is no "silencer" on a 335i unless you want to call the stock intake one, however the 135i's have a piece that extrudes from the charge pipe that is supposed to muffle the sound from the DV's.

[N8N]

Gotcha. After searching, looks like you're correct. Apparently there is both a secondary carbon filter and some kind of resonant silencer thingy on the N52 that the N54 doesn't have.

[corbs09]

There are baffles in the top of the stock intake box that act as "silencers" you will not get much more noise from the turbos by removing them however, just a little more response.