When I turn the car off there is a soft vacuum noise under the hood, problem? on 2005 Mercedes-Benz SL500

The vacuum noise is quiet and last for maybe 2min, but I'm concerned, please help? Thanks

by in Fayetteville, GA on December 03, 2013
2 answers 1 comment
ANSWER by on December 03, 2013
Possible brake booster leak. Have it checked.
COMMENT by on December 03, 2013
Ok great. Thanks for your expertise
ANSWER by on January 17, 2014
I am a member of the Mercedes Benz Club of America, Lone Star Branch, and we had a tech session at our local Benz dealer sometime back where this was discussed. The dealer tech rep said that "lots of stuff continues to go on under the hood when the car is shut off, and this is normal". For example, fans continue to run to purge the cabin filter system. I would suggest you let the dealer's rep listen to the noise to see if it is "normal" or not. This assumes the car drives without other problems, and this is your only concern.