GSXR,

Thanks for the response. Now that I'm back in town I can commence to wrenching.

My vacuum pods are all good. Two of the dual-chamber pods have a very, very slow vacuum leak because on each pod one of the four tabs that holds the assembly together snapped off. I'm finagling two replacements, so it should be rectified shortly.

I get about 3" Hg at the manifold input. When I plug off all of the lines at the five-way connector in the engine compartment, save for the line to the vacuum pump and the line to the HVAC, pressure at the manifold input jumps to 22" Hg. However, pushing the buttons on the control panel still does nothing. This leads me to believe I have both an electrical issue and a vacuum issue.

The five-way connector is new as of today and I replaced whatever else I could with universal vacuum hose. I plugged the lines that went to the auto trans that's no longer there. I'm going to have to order some of the more unique rubber tees in the engine compartment.

My blower motor does not maintain a steady speed on high, which leads me to believe the regulator is bad. Would this effect the HVAC blender door buttons?

Thoughts?

Many thanks,

Corvo Gold
1987 300TD, converted to manual shift