OK, I've read all of the "dash rattle" threads that I can find on NAM. Unfortunately, I haven't found anyone who is describing a problem that sounds similar to the one I've run into.

On my 07 R56 MCa, there's a small silver box underneath the dash on the driver's side. If you look up from where the pedals are located, you can see the box plain as day. On my lovely MC, this box rattles like all hell. Tap it gently and the rattles start. Tap it gently a bunch (similar to the vibrations encountered on just about any road) and it just "sings" with rattle-y noise.

Dear God, someone help me fix this thing.

(Thanks in advance to those who will certainly suggest taking it to the dealer, but mine's an hour away and I'd really rather not take her in for this niggly thing.)

A few questions / issues with this box in my car:
- What IS this box? It certainly looks like some kind of CPU...
- There are two bundles of wires that clip into the underside; can I simply pull these out so that I can better insulate and attach the box to the firewall?
- My box is only anchored on the left side of the firewall; the mount has an anchor position on the right, too, but it's not being used. Is this single-side-mount a mistake on my car? I'd kinda like to drill a hole and anchor the right side, too, if I can.
- Aside from wiggling around enough for the box itself to rattle, I'd swear there are wires INSIDE the box that are rattling, too. Can I open up the box and better secure the wires inside?

I really love this car, but this particular rattle (one of only maybe two in the car) is slowly driving me insane. The "turn up the volume on the stereo" solution isn't always an option.

Has anyone encountered this rattle source before? Are any solutions posted already?

Thanks very much for your help, NAMers.

 

Have not heard/experienced that one, but you have done all the investigative work. Now you can take it in the dealer and do a ride along with a tech and then they will tighten whatever needs to be tightened. This is granting that the dealer isn't too far. I know a lot of rattles can be self fixed, but that one may be rare and possibly hard to get to so better putting the responsibility on the dealer.

 

Definitely take it to your Dealer. Our Dealer has already fixed 2 Rattles for us, with Less than 6,000 Miles on the car. I won't hesitate to take it back if they re-appear or more show up.

 

If it is the box I am thinking of (just above the brake pedal and gas pedal area):
That box is held by a clamp (the metal band looking thing going around it). You should be able to see the screw/bolt that tightens the clamp. I'd try to tighten that first to see if it fixes the problem. If it doesn't maybe loosen the clamp and put some cardboard or something between the clamp and the box and retighten it. Hopefully the wires inside the box aren't actually rattling. If they are maybe you could put some foam between the wires to keep them from rattling.

 

That's exactly the box I'm referencing! (Any idea what it actually is?)

Yeah, I've tried that already. Unfortunately, to no avail. :(

I'm quite obviously an idiot for not having thought of this before! Good idea!

Honestly, I really think they are rattling inside the box (as well as the box rattling all by itself) -- what a PITA, no? It seems like I'd need to unplug whatever wires are plugged into the bottom of this box if I have any hopes of getting it open for a simple foam addition. If this is true, I find myself back at the first question above -- what IS this box? Can I just unplug these wires without concern?

Anyway, I doubt anyone knows for certain unless they've monkeyed with this box themselves... Bueller? Bueller?

 

Sorry I have no idea what the box is for, but judging from the number of wires it must be important!

 

Have seen 3-4 of these recently... Check to make sure that both nuts are tight on the bracket holding the "box" or Transmission Control Module. If they are both tight Just gently push the bracket to the right or left thus tweaking the bracket. I have not had one return yet with the rattling.