The first set of problems you describe sound very much like a disconnected vacuum pipe between the engine and the transmission. (mechanics.stackexchange.com)
LIGO's twin interferometers bounce laser beams between mirrors at the opposite ends of L - shaped, perpendicular, 4 - kilometre - long vacuum pipes, as shown in the diagram below4. (faith.org.uk)
Are you talking about vacuum pipes that are used to move the flaps that control the flow of hot / cold air into the cabin, or are you talking about using a vacuum pump to test if your A / C refrigerant pipes are leaking? (mechanics.stackexchange.com)