i have a similar issure with the discussion. i have a 2000 grand prix gt 3.8 series 2. generally stock. just bought. my heat and ac worked just fine when i bought it a week ago. now when i turn the dial the heat nor the ac will blow out? all fuses are good for hvac and hvac hi all relays are good in the car. im hearing it could be my blower motor or my blower motor resistor. i know how to replace them both... but is theere anyway too test the resistor so i dont replace that first and that not be the problem? (just trying to save every penny possible for the thrasher shift kit and perf. chip) any insight would be greatly appreciated.
thanks