Typical symptom of low charge. With the system operating, look for bubbles in the sight glass on top of the receiver / drier. There will be no bubbles if there is a full charge of refrigerant.
If you have a slide lever for the temperature, run it all the way to full hot, then to full cold. Don't know about trucks, but the minivans had self-adjusting cables. Condensation causes rust that causes the temperature door to stick, then the cable continues to move in the self adjuster mechanism without moving the door. It will appear that you're moving the lever, but the door isn't moving with it.
There have been a lot of intermittent problems with the H-valve on the firewall. A specialist will determine if that is the problem by interpreting the high and low side pressure readings.
Caradiodoc
Wednesday, June 24th, 2009 AT 1:57 AM
