I live at least 5 minutes of 15mph streets away from the highway that I usually drive on (I think the turbo gets to relax before I shut the car down), so I am pretty sure that it is not the turbo. Besides the noise comes from the EGR valve, just behind the passenger headlight- at least 18 inches from the turbo.

I guess I am really wondering what happens to the vacuum that is built up in the vac system when you turn the car off. For the locks, it is trapped behind a check valve, but on the engine side of the firewall, I don't know what exactly happens. Does it immeadiately dissipate or does it leak out somewhere- like the EGR valve....

thanks

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84 300TD - 235k - Farbe "Surfblau" bought at 213k
87 300SDL - 131k - Farbe "PimpGold" bought at 115k
00 Klepper Faltboot Expedition Double