Mike_L

Need help ASAP, have the car apart. Where does that hose that comes from the bottom of the airbox go? I kinda want to cut the bottom of the box off, to open it up under the car. The Injen intake that I'm installing has no provision for that hose, so is it safe to leave open? Should I clamp a breather filter to it and zip tie it to the fender? What does it go to? Does it need clean air? If I leave it open, its gonna get clogged with leaves. I just dumped a bunch out of the box.

NVThs1

Can you see at all where it goes? I did not take my box apart when I did my intake. What kind of opening was in the bottom of the box where that connected to? Sorry I can't help, but I left the box intact to prevent heat soak. Speaking of leaves, I should most likely clean mine out. I never made a good seal where the pipe and air box connect.

Mike_L

Can't see where it goes from the top, and I have no lift. Theres just a 1.5" hole where that tube clips onto. Looking at the picture below, the pipe in the upper left goes to that tube running under the box (and into the stock filter). I made a small cutout around it to get cool air in from under the car, because otherwise the only inlet is the stock one, which I see as being too small and the likely reason this intake shows very small gains (since the Injen on the same motor on the S4 makes like 5x as much). And, of course, I removed that stupid flap that keeps the air duct from blowing air right on to the filter. No idea why its there, but it was just 2 torx screws, so I removed it.

Mike_L

I'm getting the feeling that it might be for the A.I.R. pump, because I don't see anyplace else for it to inject the recirculated air.

If thats the case then I'm just gonna cut it out, stick an old sock over it and shove it someplace in the fender.

EDIT: Yep, stuck my phone in there and took a pic. Found it goes to part number 079959231A, which is the Secondary AIR Pump.

Mike_L

No whine with this intake. Not happy. Gonna try it without the airbox and see what I get. Don't really need to worry about the heat when ambient is under 50°. If It whines that way, I'll make a heat shield instead of using the box.

NVThs1

Let me know how it all works out. At this point where I leave, the temps are down. I wouldn't mind a heat shield in the summer and exposing the filter myself.

Mike_L

I'll probably get to it either Sunday or Monday. I want to do some logging in the regular configuration first so I can see any differences when the box is removed. I like to have hard data to back changes up instead of just the butt dyno.

EDIT: Uh oh. The ECU isn't reporting Intake air temps or knock retard to the CANBus, at least not in a format that ELM327 can see. Not good. Gonna have to just watch the O2s and IPWs and see if its adding fuel to compensate for higher temps and knock. I'll check VCDS tomorrow and see if it tells me anything.

Mike_L

Couldn't log it, so I just did it. Hallelujah, we have WHINE!!! Its not as strong or loud as the CTS-V or GTP (or especially a Terminator Cobra), but its there, anytime the car is in boost. Next best thing to a boost gauge.

And now that I was able to take a good look at the airbox, I noticed that its 2 pieces. I'm going to make a heat shield using the bottom and going up to about the same height as the top. Its much easier than having to profile the fender to make a complete shield. Get a piece of stainless or aluminum, cut it to match the stock side, put a piece of rubber weatherstripping on top (so I don't cut myself) and rivet it to the stock bottom. Easy solution. And since the filter is still exposed, it should still whine.

Heres a shaky vid. You should be able to hear it somewhat if you turn up the volume. I need a better camera and a mount.