power door locks

This is a "new" to me truck, noticed today that the Lf. side power lock does not operate from the key fob, when pushed the pass. side opens/closes but the drivers seems to want to open but it looks like the actuator is not releasing. Controls on the doors unlock both sides, the pull knob on the door panel moves a little bit but won't come up or down using the key fob. You can hear the solonoid switching but the pull knob just moves about 1/16", its trying to come up/down but not completeing the cycle. Ideas?

I would start with trying to lubricate it. I like to use a light oil.