Cold/Dry Starts - The Unofficial BMW M5 Messageboard (m5board.com)

Fuddy · 8th March 2007, 22:37

I hear a noise every time I start the M in cold weather (below 32F)

it sounds almost like the piston grinds against the cylinder wall for a second and then it's gone.

What could be causing this noise, it's almost like the sound of a vaccum space being filled.

TIA

M5inGA · 8th March 2007, 22:59

Valves, VANOS? Are you running a thicker oil?

Fuddy · 8th March 2007, 23:55

Quote:

Originally Posted by M5inGA

Valves, VANOS? Are you running a thicker oil?

I know it's not the VANOS knock because I've had that before... this is more like metal on metal noise that just happens for a split second and sounds like a whine...

I'm running regular 5w-30

IanS · 9th March 2007, 00:25

you sure it's internal to the engine? Does it do it when the engine is warm even if the ambient is cold?

Only reason I ask is because my starter went bad and would make a metallic whine when I started first thing, but if the engine was warm would not do it.

Hopefully it's something simple and external to your motor like that.

Fuddy · 9th March 2007, 01:06

Quote:

Originally Posted by IanS

you sure it's internal to the engine? Does it do it when the engine is warm even if the ambient is cold?

Only reason I ask is because my starter went bad and would make a metallic whine when I started first thing, but if the engine was warm would not do it.

Hopefully it's something simple and external to your motor like that.

it doesn't do it at all when the engine is warm, only on really cold mornings

Beamer_usa · 9th March 2007, 05:07

The TWS 10/60 is real thick so when temps. are below freezing, your bound to get some type of noise. Nothing really you can do, except don't start during winter months. Cold starts are the enemy of all internal combustion motors

Fuddy · 9th March 2007, 11:48

what's funny is that I used to get the same noise in my e30, but since the car has 275k + I dropped some lucas oil additive to it and never got the noise again.

I'm afraid to use it in the M

Brooklyn M · 10th March 2007, 02:11

i hear the same noise on really cold mornings also, but im scared to find out the answer

m3amg43 · 11th March 2007, 21:32

I hear the same noise as well!