The electronic climate control on my car almost invariably keeps the cabin temperature far cooler than the setting would indicate. Otherwise all else seems to operate well, as in the cooling mode, opening and closing of vents, etc. I believe that the vacuum line that pulls air past the sensor in the dome light is the black one that comes off the manifild, right? The one-way valve at that point works well, as does the other one that provides vacuum for the overall system. The line to the dome sensor isn't plugged, and I cleaned the dust off the sensor last year. The sensor is from a salvage yard car, and it behaves no differently than the original one. Is my control unit likely bad? Any other guesses?