I have a 2002 Chevrolet S-10 4.3 V6. I have replaced every A/C component, compressor, filter dryer, orifice tube. condenser, evaporator, high and low pressure lines,low pressure cycling switch, and blend air door actuator. Evacuated and recharged with 134a DuPont refrigerant 1.75 lbs. Fan clutch is working properly. All parts were new parts not re manufactured. I have already swapped out the compressor once the filter dryer, and replaced orifice tubes. No matter what i do the evaporator temp will not drop below 85 degrees. My pressure readings a acceptable, compressor, pulls and pushes as expected. It will not cool, I don't know what to do, I have spent more on this A/C than I paid for the truck. Please someone help? Thank you