hvac control

[scottsc4]

most of my air/heat is coming out of the floor and defrost vents regardless of where I have the setting on. very low air coming out of the upper vents when I have the control on max a/c. Isa this vacuum related or do I have a door stuck in the dash someplace?

 

[vetteoz]

Not sure about '84 but later models have vent position control by vac pots fed vac from a port on intake manifold through a one way valve by dist.
Vac line runs inside car as part of main wiring harness .
Is common for the plastic line to get brittle and break off flush with the harness in engine bay so you have to dismantle the harness to find the broken end
Grey rubber right angle fitting on right of one way valve is on end of the plastic line out of main harness on firewall

 

[scottsc4]

Thank You vetteoz, have found the connection now to find where its broke. let the fun begin! will keep you posted. while we are this subject of being in the area of the distributor I have found a female brown connector unplugged from who knows what right by the distributor or is this a possible plug for an option of some sort?

 

[boomdriver]

Thank You vetteoz, have found the connection now to find where its broke. let the fun begin! will keep you posted. while we are this subject of being in the area of the distributor I have found a female brown connector unplugged from who knows what right by the distributor or is this a possible plug for an option of some sort?

Does the Tach work?

Oil pressure?
Oil temp?

If all that stuff works and this brown plug is semi-square like it fits into another half, that might be the wire out of the harness that is for setting the base ignition timing and it needs to be plugged in to its other half that should be floating around between the distributer and the brake booster, down with the harness. Look around there to see if you can spot the other half.