I have a 1991 420SEL and the driver's window operates slowly. When I press the down switch it does not move at all. I have to hold down the switch for a good 10 sec or more to get it to open. When it does open, it rolls down slow at first then builds up speed. It consistently operates this way. It never opens quickly like the other 3 windows.
1) What would be the most probable cause? Dirty switch or worn/dying motor?
2) If it's the switch, how can I remove it? The switch on this model and year is UNDER the wood panel. Any tips on how to get at it? The center console has a lockable storage space.
3) Any other possible causes...relays...etc?
Any help would be greatly appreciated. Thanks in advance...this is a great site!