A motor will pull a lot of amps. However, I don't think your motor is getting weak. It's probably your ground. The power windows and door locks are grounded to the door. That's not a great place for a ground, especially over time with rust, dirt and grease. Also, the current for the windows is drawn through the switch. Not a great thing to do. Those switches and the wiriing tend to burn. If you want your windows to run correctly, you need to install four relays and do a little rewiring, including running a ground line from the power window motor fastener, through the boot to a suitable ground place under the dash.
This topic was posted on the TAC "Tips and Tricks" prior to the crash. I shamelessly copied the thread and saved it in my computer. In that thread, the writer came up with a new design for the power window circuit. I took his narrative and created a very crude wiring diagram because I'm going to implement this during the coming summer. If you want copies of the documents, PM me and I'd be happy to send them to you.
This doesn't answer the question that Banditboy 21 asked though. I'm not sure how many amps a properly working power window motor would draw. I don't have a way to measure it because I don't have power windows installed .... yet.
