1987 Porsche Ambient Air Valve Question!

[87fast911]

I recently purchased a carerra, with the 3.2 engine. I noticed when I did the oil change, I could not open the oil cap to check the oil, without the car stalling. So after some research on here, I came to the conclusion that I do not have any vacuum lines hooked up to the ambient air valve, which can be the cause of the car stalling when I open the oil cap with the car running. However, I do not know where these lines go, any help would be greatly appreciated, here are some pictures. Thanks.

[mnez]

Try capping both ends with a couple of those rubber vacuum caps from a an auto parts store as a test. As I understand it, that valve only functions in cold weather to draw some warm air from the oil tank when the temp switch on the manifold opens to let the air pass into the second small hose. The end at the oil tank should be capped if not in use. I also see the big vacuum line has been capped. The other end needs to be capped as well.

[87fast911]

So I should cap the 1 temp sensor port. (on the right) and the 2 ports on the ambient valve, correct?

[Autoban]

If it's my car I would wonder why one of the POs removed the lines. Porsche designed this for a purpose, so I would hook everything back up and see what happens. The PO maybe removed them to mask another (much larger) problem.

[87fast911]

The 3.2 is swapped into a 79'SC with a newer body swap.

[KTL]

Take a look at the parts diagram for the throttle body area and you can see where those hose connections go.



The small port on the thermo valve (part #13) under the throttle body goes to the air valve (part #31) and so does the hose (part #28) that has the CV bolt plugging it on your car.

Also, you should check one of the oil tank hoses that connects behind the filler neck. One hose goes from the engine case to the oil tank (part #26) and the other goes from the throttle body rubber elbow to the oil tank (part #28). The hose from the rubber elbow to the tank should have a restrictor piece in it (#7) and this is used to help the stalling condition when the tank cap is removed.

[87fast911]

Thanks!