Whistling noises

Lately I 've heard a whistling noise from the engine bay. The rubber grommet between the brake booster and the check valve leaked a bit of air. Upon closer inspection I also discovered another bodge of a previous owner. Apparently somebody broke off the little tube on the forward end of the valve and sort of glued the hose onto the valve housing:
The old check valve:

Missing tube and "glued-on" hose:

Old and new:

Rubber grommet: Spot the difference in diameter between new and old!

Final assembly: Another problem solved!

 

Final remark: After I ordered the valve from Porsche, I found out that the same part number (477 611 933 A) can be purchased from Volkswagen Classic Parts for half the price!

Porsche: 36,39 €

VW Classic : 18,96 €