I have a 88 foxbody, im having issues with my passenger window where it will go down fine but it wont go up (might go up every now n then). I replaced the window motor and have the exact same problem as when I started. Its the same from either switch, i have checked the wiring before replacing the motor and had voltage going to both sides of the motor....Not sure what the issue could be. I have tried three motors all together including the last one which is brand new, the others were used but all of them give me the same result. Anybody ever ran into this kind of problem and have any suggestions on what to check???

 

. then i guess there is something wrong with the panel the window is fit into or with the window itself (in the second case)

 

Does the window slide up and down when disconnected from all the mechanism? Does the motor operate the mechanism without the window attached? Sounds like it is a matter of some minor track adjustments and lubrication.

 

No i can move the window up and down by hand very freely. I considered the window track being a problem but i have the motor removed and still plugged into the car and it does the same thing. The motor goes downward but nothing happens when i hit up. On very few occasions it will work but mostly it will not do anything going up. Could it be a grounding issue? and if so do you or anybody know where that is grounded into?