AC Problem

[GMAN]

I just had my heater core replaced recently. Now, when I turn on my ac by pressing the Auto button, air comes out of the bottom, and not through the vents. When I press Max AC, it works great, and blows through the vents. Also, when I raise the temperature to 90 degrees, it does not get hot. Any ideas?

 

[Mr John]

What year Mark? Seems like whoever installed your heater core did not install the vacuum lines correctly and also may have broken the blend door actuator. The wrong connections of the vacuum lines will not let the air flow out of the proper vents or ducts. The temperature blend door electrically adjusts the temperature of the air. There is a small connection that is prone to breaking and this may have happened to you. It is mostly appicable to the Gen 2 cars. After the blend door actuator is replaced, the person should have just turned on the key to the run position to automatically calibrate the actuator. It may be as simple as that. See if you can regulate the temperature manually by setting the temperature up and down, leaving some time in between to see if the system can output the proper temperature. If it can and won't do it automatically, it could be as simple as not connecting the in car sensor elbow on to the blower moter. That sucks in the ambient air from inside the vehicle to find out what the inside temperatured is and then it regulates the air coming out of the heater/A/C plenum to keep the temperature correct. If you can do some work and can get the radio out of the car, maybe the vacuum hoses are connected wrong, but I need to know the year since it changes from year to year and they are not always the same. I also may not have the correct year you have, but somone should have it here.