Grumbling compressor

[996jimbo]

What might be the deep grumbling sort of compressor noise that I hear from my engine? It goes off periodically, doesn't seem to be connected with any particular thing that I do.

Car is a 2004 E320CDI.

 

[Major774]

SBC pump, part of the brake system.


Nothing to worry about until you get a red warning message on your dash.

 

[Spin_bowler]

Do you have airmatic?

 

[996jimbo]

I don't have airmatic (at least I don't think so). I had a hunch that it was brake related so am grateful for the above advice!

 

[Alps]

as above, SBC pump