1985 GTSI Window motor

When I replaced the grease in the motor housing it solved the issues. Cleaning the cable and pulley system also helps. I went further and replaced the window track felt. That made a huge difference.

 

It's been about 10 years since I did this so bear with me..

Can only be two scenarios given that you haven't changed any of the operating parameters.
- you have the regulator installed upside down. ( I don't think that's even a possibility )
- Too many wraps on the drum. When I say "loose " i'm talking about possibly an inch of play. Once I cycled the motor everything adjusted properly with start/stop sequence of the cable travel.
- pretty sure the cable didn't shrink LOL and it fit properly when you disassembled. Hang in there man!

 

Absolutely. By having it go outside of two posts you have shortened the effective cable length. On my 78 GTS I have one post between the cable and they have to enter and exit in the right place.

Look at the other door and see how the wire is routed. Also check the motor and housing orientation from the three mounting screws.

 

May be a picture here will help others visualize your actual set up and possible diagnosis?