Temperature door motor issues 98 park

[73GMC1500]

1998 park avenue 144 thousand miles. I bought the car about 6 months ago. The drivers side temperature blend door motor was inoperative. As a temporary measure( because I didn't want to spend the money on the motor at that time), I took it off, took it apart and turned the gears so it was set on hot. Put it back on, left the wiring connector unplugged. This got me thru the winter. When on floor, both sides blew hot. Now that it's getting warmer, the auto climate control wants to go to mid/floor after a short time. When it did that the drivers side blew hot air (obviously, with the inoperative motor) and the passenger side dash vents blew cold.
This was starting to drive me crazy, so I broke down and ordered a motor from rock auto. Installed it, now we have new issues. Most of the time the left side goes back and forth from hot to cold, to almost no airflow sometimes, every few seconds it will do this. Sometimes it will stop after say 20 minutes but usually stops on cold when I want heat.
The passenger side temperature motor seems to be working properly, when I'm in manual, on mid, with the blower on high, turn the temperature up, right side gets hot, turn it down towards 60, and it gets cool. Meanwhile the drivers side seems to do whatever it wants.

 

[ryenie]

Does the temp display flash after you first start the car? I think it's recalibrating itself when all the doors are going through their motions. If it can't calibrate after so many tries you may have another actuator that isn't operating as it should, or a stuck door. Mine hasn't been able to calibrate so every time i start my car i have to go through this (haven't had the time or the money to fool with it either). Most of the time, if i turn the temp all the way down, then all the way up, it will allow the heat to flow without having to manually move the arm for the actuator that controls the temp.

 

[73GMC1500]

No it doesn't flash. Some online searching I've done indicates the system needs calibrated if any part is replaced, and to do this, turn the system off, disconnect the battery for a few minutes, reconnect, turn the ignition on, but don't start, and leave climate control off. This will supposedly recalibrate the door positions.
Maybe I'll try it today while doing the rear brakes. Not out anything if it doesn't work