My Scion XB 2008 again is having issues.
When i try to out it on reverse it starts to stutter and turn off or gets stiff when trying to steer it.

Already changed the alternator, fusible links, power steering and only works well for a while

Im at my wits end with this car. Now I dont know what it could be.

 

Only in reverse?

 

well most of the time is in reverse since i back out of my drive way and it starts shaking and gets stiff and wont turn. but sometimes i can get it into drive and it will not turn left and shakes like it wants to turn off

 

Nothing wrong with your power steering.

The power steering is electronic....if the engine is stuttering, it's not making enough electricity for the power steering motor to function properly.

Fix the engine stutter and your steering will be fine.

That being said, are there any OBD codes?