More than likely, one of the plastic clips that hold the rod in place, has broken. Unfortunately, the only way to get to it is to remove the inner door panel. Not 100% sure, but in most cases, it can be removed with the door closed. Will not be a fun repair, but not expensive either.
Loren
My 1992 chevy lumina 4 door sedan has a drivers door that won't open. The solenoid when pushing the lock position or unlock position on the door appears to be moving a rod. However when I put it in the unlock position and then pull the mechanical handle to the rear the door won't open. This occurs with the mechanical key lock in the open position also. Help

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