I took the intake silencer off to do the silencer mod and found this hose just sitting here. Is this a vent hose for the transmission, or did it come loose from something else?

It seems that it was connected to something because the end is deformed like it was connected to a fitting.

2007 Cooper (not S) automatic transmission

 

That's the breather hose for the auto tranny. That's how it's supposed to be.

 

Really? I'll buy that. Thanks for the info.

 

I asked the same question about 6 months ago, that's what it is...

 

i concur with dr. oxybluecoop. now i'll know what that is when i do the same mod.