My air filter started humming today! I did the check valve fix, ran around doing some errands (about an hour of driving), and went in to work. When I got to work, before I shut the engine off I noticed this strange noise. I pinpointed it to the SC air filter.

There is obviously some sort of resonance going on, only noticeable at idle. Can't find the right size screwdriver here at work to get the cover off, so I'll do that later.

anyone else with a SC have this happen?

 

I don't have a sc yet, but I can guess about the noise. The supercharger rotor is spinning down. It should be smooth, there shouldn't be any resonance, but it sounds like it's passing through some rpm regime where it's generating a harmonic resonance. Maybe as it spools down it loses lubrication. I have too much time on my hands.

2x6spds

 

Mine does the same thing. The hum goes away with the cover off.

 

When I dropped a K&N filter in my stock air box it hummed. The cool air intake had a similar sound. I haven't listened to the airbox much with the SC since the whole thing makes a noise. Maybe I'm used to the humming.

Wesmaster

 

Well, either mine didn't do it before or I never noticed it before. As long as it's not indicative of a problem or some weirdness going on, it doesn't matter to me.

 

[QUOTE]Originally posted by rocketman
[B]My air filter started humming today!

 

The resonance you are describing could be a couple things. First thing to try is loosen the three bolts that hold the air box brackets to the chassis. Push down on the box while tightening the three bolts. This gets the box sitting as low as possible. The only other thing is the air box lid itself. It's only two layers of carbon fiber and can have a tendency to "drum" from the air movement. There isn't realy any more room between the hood and air filter element to try and make it thicker or stiffer. It's just one of those things that happens.

 

The Comptech foam filter hums.. SC or not. I have the filter and it hums in the stock airbox.. works great so I have not worried about it.

 

Hey Silver shouldn't that be ZOOM, ZOOM, ZOOM....not HUM,HUM,HUM?

Oh sorry that's the new Miata......

 

[QUOTE]Originally posted by Utah S2K
[B]Hey Silver shouldn't that be ZOOM, ZOOM, ZOOM....not HUM,HUM,HUM?