When I turn on my rear wiper it starts and stop midway and periodically..Any ideas?

 

My first guess would be the motor going out.

 

motor brushes could be worn out, or there could be something catching on the arm or shaft that goes into the back, either way sounds like you need to open up the liftgate and take the interior panel off and see whats back there.

 

It also could be corrosion on the harness where it plugs in.


But my gut feeling is a motor going out.