Why is smoke coming through my car vents?
A damp chemical smoke/steam/smell from vents. It could be the heater core. This small radiator device is buried in the dash, and hot coolant from the engine flows through it. With age or neglect it can start to deteriorate and leak into the vent system.
Where does the vacuum line from the defroster go?
Vacuum lines travel from the vacuum control switch on the dash to vacuum servos under the dash. These servos move the air doors which turn on and off the defroster. If you can hear a hissing sound when the car is running from under the dash then vacuum is escaping.
What causes air vents to stay in defrost position?
If you have an older car then the defroster system is controlled by using vacuum supplied by the engine. Lift the hood and inspect the vacuum hose or tube that leads from the intake manifold to the passenger’s side firewall. The image below shows a typical line break which causes the vents to stay in the defrost position.
Why is my car a / C blowing hot air out of the vent?
Your car’s A/C system is one that operates a little differently than you might think. Instead of actually creating cool air, it instead removes the heat and moisture from the air inside of your car, leaving you with cooler feeling air.
Why is my defroster not working on my car?
A control switch on the dash can fall apart allowing the vacuum to escape and not reach the servos. A defroster can also fade when traveling up a hill but then return once the grade is overcome which is a signal the vacuum check valve has failed.
Why is the steam vent on my radiator not opening?
Steam vents on individual radiators or main steam vents may not be opening when they should. If an individual steam radiator vent fails to open, that radiator won’t get hot even though its supply valve is open.
Vacuum lines travel from the vacuum control switch on the dash to vacuum servos under the dash. These servos move the air doors which turn on and off the defroster. If you can hear a hissing sound when the car is running from under the dash then vacuum is escaping.
If you have an older car then the defroster system is controlled by using vacuum supplied by the engine. Lift the hood and inspect the vacuum hose or tube that leads from the intake manifold to the passenger’s side firewall. The image below shows a typical line break which causes the vents to stay in the defrost position.
What causes a defroster door to get stuck?
In some cases an electrical motor can burn out or the gears inside the actuator can break causing the defroster door to get stuck. A climate control system can stop working after a battery replacement as the control prompt of the system is lost and needs to be rebooted by removing the defroster/heater fuse for a period of time and then reinserted.