Recently picked up a 1978 BMW 320i California model (emissions deleted by the PO). I am trying to work out a fast idle, ~1500RPM. Vacuum lines checked and replaced as needed Vacuum pressure ~20 and steady. While researching I came across a thread about setting the idle and adjusting the idle screw. When I tried to adjust the screw I discovered that the screw was actually absent and had been replaced with a vacuum cap closed side down. My question is the diagram on realoem (1978 320i>Fuel Prep>Fuel Injection>Throttle Housing assembly) shows the assembly and lists a Throttle Screw (PN 13541261429) and O-ring (PN 17211742635) that looks correct (#25 and #24 on the diagram) but the line goes to the incorrect place. The screw location looks to be on #29 in the top hole. Is the diagram wrong or is that the incorrect part or am I just misreading the diagram?
Idle screw replacement
