Oldsmobile Questions? Ask a Mechanic for Answers ASAP
Im cam and ill help you out the best i can!
It sounds like one of the blend door actuators is defective. Im assuming that you want heat this time of year and the passenger side is operating normal and its the drivers side that is not, so i would target the drivers actuator.
It is located behind the driver knee bolster above the gas pedal.
These are a high failure rate and extremely easy to change.
I would remove it and switch from hot to cold and see if it moves. IF it does not than you can either relace it or you will have to test the circutry.
you can even give it a tap and see if it starts to move than.
IF its not the actutor than it will be the control head, but the actuator is the more likley cause.