I have a 2000 Oldsmobile silhouette with the power slider and it doesn't work very well-If you push on the outside of the door with your hip just below the handle and push the button on the remote or the button inside it will open.Once open it shuts just fine with either button.

 

Maybe you could be a little more specific. But if your power is moving the door just fine could the door possibly be out of alignment and or could the latch be messed up or getting caught?

 

I figure that something isn't ligned up right or not making a connection.The power part works fine and it closes fine it just doesn't open without assistance.If you push the button to open and then use the handle on the inside of the door and push it open a little it will open itself when you manually start it and if you push on the door just below the handle and use the open button on the remote it'll open