Here's the way it is on my 86 535i. There are 3 vacuum lines.

#1 from the port on the lower front (underneath) of the intake manifold to a nipple in the middle of the line between the top of the valve cover and the middle of the manifold (PCV).

#2 From the port on the lower rear (underneath) of the intake manifold to the fuel pressure regulator.

#3 From the bottom of the throttle body to the thermal switch (green) on the top of the thermostat housing. This switch has 2 vacuum connectors. There is what I'm guessing is a check valve in the line between the throttle body and the thermal switch.

From the other connector on the switch to the canister purge valve (located on the rubber air passage between airflow sensor and throttle body).

Mike L

Does anyone out there have a diagram on the routing of engine vacuum lines on a '86 535??

The guy I bought the car from had all the lines and wires mixed up so nothing worked properly. I am trying to sort it all out and I have a few ports left open with nothing to attach to them.
Any help is greatly appreciated.

Thanks,

Tom in PA