“Most likely” the motor. Known weak point. I’ve heard of bad regulators but # of complaints about bad motors is about 199:1. Got my current Z (2003) from orig owner in 2013. He had replaced both motors when car was 5 years old, then again just before he sold it to me. And now, they’re both doing that “auto-up-goes-to-top-then-drops-five-inches” thing, tell tale they’re heading for failure.

 

My daily driver is out of commission currently so I have been driving my 350 everyday. It sat a little longer than I would have liked and the first thing I noticed was the driver's side window was having issues. I've been limping it along for a couple weeks, but I hate driving with the windows up. It got real bad a couple days ago (i.e. wouldn't go up when I did the shut the door method); I finally got it up (the window) and started driving with the A/C on and windows up. Well I just HAD to get Taco Bell today and it ended up sticking all the way down after the drive thru. Luckily I tried the bang on the panel method and it worked. Not super thrilled that it's something else that I have to fix, but at least it does present the opportunity to paint the switch plates. I have been so careful with them but somehow they ended up looking like sh*t.