1. Is the vaccum at the diverter valve on when the heater is on or off when the heater is on? (Maybe a better way to put this... At what slider position is the vaccum signal sent to the diverter? )

2. What are the two small, hard, black, plastic lines that come out of the wiring harness near the passenger side head?
Is there any way to tell these two apart?

Vehicle is 1991 Formula

Thanks for your help!

 

In my 88 TPI, there are 2 small black vaccum hoses in the pass side wire harness running thru the firewall. One hose runs to the heater bypass valve and one up to the plenum area. The other end of the 2 goes thru the firewall and to a purple and a grey vaccum hose controlled by the heater console lever

okay i found this in the archives...it sort of answers question two, but can someone please expand? Thanks