Vacuum questions 1979 911sc

[Ngrich99]

Did I spell vacuum right? Anyways I am bringing this car back to life after an 8 + year sleep in the back of someone's barn/shed/garage. It now starts runs drives and stops after working on it for 4 months in my limited spare time. It has a lean cold start issue that I am working on. I replaced injector seals and sleeves and cleaned and tested injectors. I hooked the smoke machine up through the air box and no leaks. Smoke did come through the hole between the boot and the fd where the mixture screw is. Would this be normal ? Im thinking it would be as the hole to stick the Allen is in the top of the air box. Also the smog pump is disconnected. Is the yellow cap in the pic for the vac line that would have gone to the pump? Thanks ! This forum has consumed a lot of my hours but has guided me through waking this old girl up.

[ninelevenick]

Correct me if I'm wrong, but I believe performance zapping vacuum leaks occur after the throttle body. I'm guessing that the small amount of air escaping by the FD is inconsequential. I'm not near my car right now, by I do think you are correct about the capped air outlet being designated for the air pump. Again, someone please correct me if I'm wrong.

[Ngrich99]

Here is another pic of the capped vacuum port that I'm wondering about . Anyone tell me what his was originally for?

[gregoryp]

On my 79' I believe that went to the air pump and I plugged it when I removed it.

[Ngrich99]

Thanks guys

[Flat6pac]

The yellow plug should be the vacuum retard which isn't used on a 78/79 distributor. It only vacuums with the butterfly closed. 1980-83 uses this connection for the retard on the distributor.
Bruce