Questions & Answers for: gmc heater vacuum leak

...gmc jimmy defroster-heater blower will not direct heat My 2001 gmc jimmy has good heat, and blower levels work. Heat will only blow through vent and not to defroster (windshield). you have a vacuum ...

Heater will not go off of hot air even if control is in off position Most heater controls are controlled by vacuum. Check the vacuum hose going to the firewall, on the heater side of the car, for ...

GMC 5.7 4x4 extendacab 3 door 1500. i am not getting heat. i changed the heater core and the thermostat. i checked the oil to see if i had antifreeze ana water in it but there is none in the oil cause

...gmc sanoma. heater dampers do not work properly. can hear a vacuum leak at rear of heater control switch. new switch at dealer is not available,junk yards no luck. the vacuum hose configuration is ...

...gmc sierra pickup - heater will not change from defrost position will not devert air to floor or dash make sure the vacuum supply that comes from the engine through the firewall by the evaporator has ...

...heater core, but no flow anywhere else. slight hissing noise though you have a vacuum leak most likely inside the car if you can hear the hissing sound.check under the passenger side kick panel for ...

vacuum leak Heater control valves if vacuume leaks out the control valve replace the control switch

...heater core and to defrost or vents. These doors have actuators which run on engine vacuum collected in a vacuum resevoir and held by a check valve. A vacuum leak, or bad check valve or bad actuator ...

...GMC dealer and check it out. For many years, the heater & defrosters of GM vehicles have used a vacuum source to operate the systems. If that is your problem, the vehicle needs to build up a ...

gmc jimmy heater runs hot when turned all the way up but runs cold if turned down even a little ? temperature all hot or all cold, no control. Have the temperature control blend door operation checked