Weird noise issue...What is it? 120D

[Stompie]

Hi Guys,

So i have been intermittently hearing this noise when i switch off the engine after a drive. It does not happen every time and does not feel like anything has been affected but now recently been noticing that my brake pedal will go rock hard while car is off. Once i turn the engine on, pedal goes soft making me think this is vacuum related.

This is not my video, but i get the exact same noise.....What is it? Can someone point me in a direction to check.

I can hear it is coming from the back of the engine/intake manifold

 

[Stompie]

Removed the engine cover now and from the location i heard the noise yesterday, it would possibly point to the vacuum solenoid/valve Number 11 on this diagram or possibly one of the vacuum lines that has perished as they do seem a little old.

 

[Stompie]

I have replaced all vacuum hoses and issue seems to be gone. the pipes were very brittle and one coming out of the solenoid seemed to have been broken.

Since replacing all piping including the ones on the injectors, the car feels more powerful, mean pullaway in 1st will wheelspin which didnt happen before so something made a difference.