MyE28.com

Does anyone know where the vacuum hose from the furl pressure regulator on the S28B35 fuel pressure regulator hooks on the back of the engine nearest the firewall. I see the hose goes to the intake to the front of center, then from the back of center rearward, but the other end isn’t hooked anywhere. Thanks.

There is a Idle speed adjustment screw that is between the intake runner for Cyl#3 and #4. You can see it from directly above the engine past the fuel injector rail. Off the front of that housing there is a fitting aimed straight forward. The hose goes directly from there to the fuel pressure regulator.

Go here and look at the diagram, it is in the throttle housing for cylinders 3/4 (#2 in the diagram) it does not show the vacuum port but it is just below the screw (#33) in the picture aimed straight forward.

https://www.realoem.com/bmw/enUS/showpa ... Id=13_1089

Hi and thank you. I think that is the piece I see. One vacuum hose goes from the pressure regulator to the part in the diagram. On the opposite side of that is another inlet facing directly rearward. There is a hose hooked there and it goes back along the intake manifolds and is hanging between the firewall and the engine. I can’t imagine a vacuum hose not connected at both ends. Maybe I’m wrong?

That goes to the interior temperature sensor under the dash if I’m not mistaken.