Since I have removed the foam nearest the cabin, I can hear a metallic, almost grinding, noise every time I put my foot down gently. Pretty sure the noise is coming through the sound generator. I have no idea if the noise continues when I push down harder as the noise of the engine / induction no doubt overrides it. Any ideas?
Metallic noise since sound gen mod
- Thread starter wilbo
- Start date
It coincided exactly with when I removed the foam. It almost sounds like a brake pad wear indicator noise when they grind, however only when I put my foot on the accelarator, not the brake! It's quite subtle and is easily drowned out by music, but I like to eliminate all squeaks, rattles etc if I can.Nova2k7 said:
There's a metal coil inside the piping which forms part of the sound generation in combination with the foam. When you remove the foam the coil vibrates, causing the metallic resonance sound you're hearing.
In my previous Z4, I chopped out the metal coil which solved the issue, however for my currently z4 i re-inserted the small foam piece to mask the sound, so now its not a problem.
Andrew.
In my previous Z4, I chopped out the metal coil which solved the issue, however for my currently z4 i re-inserted the small foam piece to mask the sound, so now its not a problem.
Andrew.
johnnymarrsbarres
Member
Mine does this too. Wondered what it was. Good to know its nothing to worry about...
Sent from my iPad using Tapatalk
Sent from my iPad using Tapatalk
Bbr92 said:
The metal coil is certainly there on the pre-facelift, as it took me about 20 mins to remove it all. When you pull the two parts of the sound generator apart (the tubes) and remove the foam, you can see the very end of the metal coil and also a diaphragm type arrangement. The coil itself is well hidden and not easy to see, I only found out it was in there as I tried to remove the metal part which I could see, and kept pulling until the whole of the coil was removed. There's at lease 40-50cm of wire coil in there.
Maybe the facelift is a different part, i'm not sure.
Andrew.
wilbo said:
I'm not sure what it's purpose is, however all I know is that this was the cause of the problem. If you remove the sound generator and shake the pipe, you can hear the coil vibrating/ratling.
I did over 15,000 miles without the metal coil in there and had no issues.
I'm only speak from my own experience here, but considering the sound generator is so easy and quick to remove, I'd sugguest you do a bit of investigation and see if the cause is the metal coil as I suspect.
Andrew.
