Questions & Answers for: GMC unit turn wont blow air

...wont blow cold air when idling, but will blow cool air when driving, not cold as it should be. Have added refrigernat (r134a) , but still not blowing cold air ..what else could it be? The refrigerant ...

...unit and turn the temperature all the way up and the fan all the way up and it will not blow any air out of the vents not even with the ac on. i looked at the fuses and they are all good. i dont know ...

...find vacuum lines from engine to firewall. Please help. Air does blow to the rear console. check you air flow position sensor should be behind radio that an electronic unit vacuum line wont ...

...turn them off and on. These are sencitive unit's now not like year's ago. A heater blower is of no use running until either the vehicle engine is warm or the air con. runs cold none of which happen's ...

...unit working fine,but when I turn the knb to heat,cold air ac unit working fine,but when I turn the kng to heat,it still blows cold air on a 1999 gmc envoy. the temperature guage reads 180 to 200,but ...

...heater core hoses off in the engine compartment and blow compressed air through, if the vehicle is using dexcool orange coolant it is probably plugged. Air conditioning unit will not blow out hot ...

...turn but it wont come off. Am i missing something? I believe its dry because my truck wont blow any warm air. push down on the cap while you turn it. There are locking tabs on the radiator that ...

...unit but stills blows warm air. The compressor works turns on and off so I dont know what the problem is ?? Aircon systems have a control valve or reversing valve which sticks due to non use.Just ...

...unit -- about an 8 to 10 hour job!). If the compressor does not engage when you turn on the A/C, see if it will run by jumping the compressor clutch wire directly to the battery (use a fused jumper ...

...turn off in the Off position. I feel it could be the Air Conditioner Heater control unit assy. but not sure how the vacuum tubes on the position switch work. Thanks WHAT ABOUT ANY FUSE OR RELAY FOR ...