I had an issue with my passenger door window motor. It would go down fine but struggle like merry hell going up.
Tried some silicon spray to no avail so got a new motor.
Fitted it to find there was no difference! Was not amused! Whilst the door card was off, I went on the overkill on lubricant spray - end result? It worked. Been fine ever since.
If you need a window motor, I have one spare out of a 51 plate

(I wasn't fitting it back in!)
Longest Serving BOO Member
Bravo: Nov 01 80SX / 75,000 miles
Coupe: Feb 97 20V N/A / 135,000 miles