there is a little electric motor located under the dash on the heater box it opens a little door in there that directs the air to the defroster, vents, under the dash etc. those are bad about going out.
If air flow is reduced when a/c is on- could be an incorrect refrigerant charge - causing the evaporator to "Freeze" When you shut of system evaporator has a chance to defrost restoring air flow. Try turn vent only on when air flow is reduced to see if evaporator defrosts and air flow restored
What temp. thermostat did you put in? Try a higher temp. one. or check to see if heater core is clogged
No
Park the truck so the front end is raised or jack it up, to get the radiator opening higher than the heater core. Then bleed the system normally by filling and running, heat on high, until thermostat opens. Then refill and top off.
54 LBS. to 62 LBS No lower and no higher.
55 PSI to 62 PSI no higher are lower are you will have starting or running problems.
the heater blows warm air when fan is on low but blows cold air when fan is turn to higher setting
try higher amp breaker
9 to 13 LBS. No higher are lower are you will have starting and running problems.
9 to 13 LBS. No higher are lower are you will have problems.
60 to 66 PSI. If it is any LOWER OR HIGHER you will have problems.
Idle speed is 200 rpm higher than normal . Possible vacuum leak.
remove it from service and refer to higher level maintenance.