2002 Cavalier Heating problems

[juniorsbud]

When I turn my defrost onto the front window my A/C comes on even if I have it on the heat. Also when I have it to go to my feet nothing but cold air comes out. What is wrong with this dang car??

[Classicrocjunkie]

Here is 58 results when you search for heater problems... try searching before you post... Same question get annoying.. there is even 3 on the same damn page without searching....

http://www.automotiveforums.com/vbul...earchid=713631

[Classicrocjunkie]

#1. When you say "I have no heat", please differentiate between "Cold air blows out of my vents" or "There is no air blowing altogether".

#2. If the case is "I have no heat", the cheapest and easiest first step is to replace the thermostat. If the thermostat is stuck in the open position, it will not allow the coolant to reach a hot enough temperature to produce heat. This is also a good time to check condition of the coolant, and flush/refill the system if it is questionable.

#3. If the thermostat has been replaced, check next to make sure your temperature control cable has not come unhooked from the back of the HVAC controls. If this happens, the air vents inside the dash will not shift properly, and one or more settings may be operating at the same time, adversly affecting vent temperature.

#4. If the thermostat is verified to be good, the coolant in good shape, and the HVAC controls operating properly, odds are, the cause is a plugged heater core. In this case, the heater core must be replaced, and it isn't a half bad idea to replace the heater hoses, since you're in the area.

Note: These diagnostic procedures are only valid if the vehicle is NOT overheating. If the vehicle is overheating and there is no heat, there is a different set of problems, and a standard overheating diagnosis should be taken instead.

[juniorsbud]

Originally Posted by Classicrocjunkie

#1. When you say "I have no heat", please differentiate between "Cold air blows out of my vents" or "There is no air blowing altogether".

#2. If the case is "I have no heat", the cheapest and easiest first step is to replace the thermostat. If the thermostat is stuck in the open position, it will not allow the coolant to reach a hot enough temperature to produce heat. This is also a good time to check condition of the coolant, and flush/refill the system if it is questionable.

#3. If the thermostat has been replaced, check next to make sure your temperature control cable has not come unhooked from the back of the HVAC controls. If this happens, the air vents inside the dash will not shift properly, and one or more settings may be operating at the same time, adversly affecting vent temperature.

#4. If the thermostat is verified to be good, the coolant in good shape, and the HVAC controls operating properly, odds are, the cause is a plugged heater core. In this case, the heater core must be replaced, and it isn't a half bad idea to replace the heater hoses, since you're in the area.

Note: These diagnostic procedures are only valid if the vehicle is NOT overheating. If the vehicle is overheating and there is no heat, there is a different set of problems, and a standard overheating diagnosis should be taken instead.

I have heat but it only blows on the dash and when the front window is on full defrost the A/C comes on...is that any better for you