2004 quest power seat problem

2004 nissan quest SE
Drivers seat won't go forward or back, it just kind of racks sideways when you try to adjust with the power setting. taking the seat out, it looks like there is one motor that drives ball screw on both sides. The motor is working, but one of the racks won't spin. i am guessing it is the small gearbox or the actual rack.
any ideas?
the picture (if it works) shows the motor, it works fine as the shaft coming out of the back of it spins (upper left of picture), the ball screw on the right is the one that is not spinning. If it manually fool with it, then hit the button, it will make about one revolution, then not move any more.
| Attachment | Size |
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| seat motor.jpg | 426.66 KB |

2004 Nisson Quest
I have the very same problem with the drivers seat. It works except going back and forth. I was told that it requires a new motor at a cost of $650. Where can I find one online?
power seat problem
I have the same problem, but the seat doesn't move backwards, I removed the switcher where all the controls are (up, down, recline, back and forth. I called the dealer and they told me to better replace the whole chair and it would cost me about $ 1600.00. Now I don't know how to remove the chair and adjust it manually so I don't have to move it anymore. Will you please help me if knowing how to fix this problem?
Thanks.
Vafiomar.