Odd rattle noise during cold start.

[mosaud1998]

Not sure if that "rattle" sound is normal or not. Just started noticing it ever since the cars been sitting outside in the cold.

76k miles on 09 BMW N52 engine

 

[bonjo]

I take it your car is not a diesel.

Does the rattle disappear and when?
Is the engine camshaft chain driven?
Is the cooling fan constantly running?

 

[mosaud1998]

I take it your car is not a diesel.

Does the rattle disappear and when?
Is the engine camshaft chain driven?
Is the cooling fan constantly running?

Nope inline 6

Rattle good away once I drive the car and it's warm

Not sure if it's camshaft chain driven
I know it's gotta timing chain no belt.

Cooling fan is never on unless yhe A/C is on

 

[pezzy84]

Does it stop abruptly after a minute or so? Some cars have a more pronounced secondary air injection rattle than others and typically it only runs for a bit after cold start. Thinking of it a few neighbors of mine have BMW 2.0T's and they have pretty rowdy secondary air injections.

 

[mosaud1998]

Does it stop abruptly after a minute or so? Some cars have a more pronounced secondary air injection rattle than others and typically it only runs for a bit after cold start. Thinking of it a few neighbors of mine have BMW 2.0T's and they have pretty rowdy secondary air injections.

I parked it in the garage today and didn't hear that noise.

Maybe it was the cold

 

[silversport]

a heat shield or something rattling/vibrating due to the higher RPMs of start up???...my CTS Sport Wagon 3.0 does something similar upon initial start up and never again...in my case it is a heat shield under the car...

Bill

 

[bonjo]

the timine chain drives the OHC with time it can develop some slack. This would cause the a diesel like clattering until the engine has warmend up.
Generally not an issue unless the slack it outside tolerance.
If the fan is not running, then the blabes will not be the cause.

are you using the right grade oilfor the outside temp?