The A/C system has recently been almost completely rebuilt. New compressor, evaporator, condenser, dryer, low pressure clutch switch, and most recently replaced Evap. air temp sensor. The system seems to cool very well in normal in traffic conditions, but at highway speed, cooling quits. Static pressure seems to indicate correct Freon in system. Most recently tested at idle for quite awhile and vent temperature was around 50 degrees with outside temp of approximately 92 degrees. Attempting to find location of cabin air temp sensor. Also any other tips to get this thing up and running properly.