BMW M5 Forum and M6 Forums banner

1 - 4 of 4 Posts

·
Registered
Joined
·
112 Posts
Discussion Starter #1
I'm getting a really diesel/clatter sounding noise when blipping the gas at idle speed (N, clutch in). I first noticed it when trying to rev-match for downshifts. Car is warmed up, no lights or warnings.

The clattering noise sounds kind of like the noise you get right before you stall.

Anyone know what this could be?
 

·
Registered
Joined
·
5,239 Posts
Hobbez said:
I'm getting a really diesel/clatter sounding noise when blipping the gas at idle speed (N, clutch in). I first noticed it when trying to rev-match for downshifts. Car is warmed up, no lights or warnings.

The clattering noise sounds kind of like the noise you get right before you stall.

Anyone know what this could be?
It is very normal for our cars. There are at least two theories - one is that as oil pressure bleeds off the Vanos chains get a little slack and this is some part of the mechanism (could be the chains themselves) slapping. It could also be the dual mass flywheel - one mass slamming against the other. Don't really know - but all M5's do it. It usually won't happen on the a second blip right after letting the engine back to idle, so I think it is oil pressure related. I do not, however, believe it is preignition/pinging - there is so little load on the engine.
 

·
Registered
Joined
·
1,346 Posts
Hobbez said:
I'm getting a really diesel/clatter sounding noise when blipping the gas at idle speed (N, clutch in). I first noticed it when trying to rev-match for downshifts. Car is warmed up, no lights or warnings.

The clattering noise sounds kind of like the noise you get right before you stall.

Anyone know what this could be?
Mine sounds also like a Diesel at idling. Asked the BMW sevice technician who was servicing on my car about it, and he says, it's normal. And a few VANOS modules has been changed here in Finland, but not many according to him. I told him to check the diagnosis, and nothing turned up, so it's a typical cosmetic fault according to him.
 

·
Registered
Joined
·
400 Posts
tell the BMW mechanic you want to have the Repair Kit of 4 toothed shafts and updated springs for gears installed.

If its the VANOS grears rattling , this will fix the problem.

Your mechanic should be knowledgable enough to know if its the gears rattling.
 
1 - 4 of 4 Posts
Top