I've been replacing vac hoses, etc. including the vac shutoff valve as oil was all over in the lines. All is well and the engine even shuts off now - most likely due to a leak I found in the green line that goes to the climate control inside. I plugged it off for now.

Now my question......I noticed while under the dash checking the vac lines to the ignition key switch that there was a black vac line hanging in space. I could not find anything that it would plug in to under the dash. Traced it back to the engine compartment and found it went to the vac valve for the trans (the one on the injection pump). I looked at all the vac diagrams I have downloaded and the references I found for this line was the term "vent to passenger compartment" or something similar. Does this line exist to just pull clean air into the vac valve form the passenger compartment If not, where does the end of the line plug into?

Thanks for your help

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