Fuel pressure regulator 300E

My fuel pressure regulator on my 88 300E has a vacuum line coming out of it. I bought the car used and the vacuum line is disconected. Does anybody know where it connects to? Thanks for any help.

[lancel]

On my 190E the Vacuum line connects between the egr valve and the idle speed control valve.

I do not think that there is an EGR valve on mine, but I am not sure.

Come on guys, somebody has to know where the vacuum connects.

[Ron Miller]

If it is what I think it is, the line from the regulator goes up to the black rubber hose that connects between the air cleaner housing and the crankcase breather.

Thanks people, but I thought that this is a vacuum hose and should be connected to some sort of vacuum source such as intake manifold or something. This rubber connection between the air cleaner and camshaft cover is not a vacuum source. I do not doubt that it may connect there, I am just curious as to why...

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On the 190E this hose is connected to a vacuum source which is the idle speed control valve. The back end of the idle speed control valve is connected to a vacuum source and I think it is called auxillary air device (basically a vacuum pump)

On my 300SL-24 the vacuum line coming out of the fuel pressure regulaotor hooks up to a black hose that links the air-filter box to the valve cover as well.