1990 GMC 1500 Pickup Q&A
1990 GMC 1500 Pickup Question: door problem
It sounds like the drivers door on your 1990 GMC 1500 Pickup is sagging. Check the door alignment just as the door is against the striker (bolt). The door should be perfectly aligned at that point. If it is low then most likely the hinges or hinge pins are worn. - Oakman
The inside and outside door handles are prone to breaking.
The power door lock actuators may become slow to operate or stop working completely and require replacement.
The glass on the driver's side has fallen down insid3e of door.
One or more heater & AC (HVAC) temperature and/or air delivery mode door actuator may fail, resulting in improper temperature or air delivery. If this occurs, fault code(s) should be stored...
One or more heater & AC (HVAC) air delivery and/or temperature mode door actuator may fail. This can result in incorrect air delivery or temperature. If this occurs, fault code(s) stored...