For quite a while now, my driver's window has been very slow to go down, but goes up just fine. The passenger window, which is the common one people have problems with due to the ground path going through the master switch (more to go wrong), works fine either direction. It gets much worse in cold weather, and is currently barely willing to budge.

I had previously swapped in a spare window regulator, and in so doing, noticed the wire running down the back of the track was frayed. I figured that was creating all the resistance and the problem would be fixed... Nope, it god bad again. Wouldn't surprise me if the "new" one looked the same if I were to pull it again. I had also tried a different master switch, but that didn't help any.

Anyway, as it's worse than it's ever been, and it isn't raining this week, I decided to dig in and try to figure it out. I'm getting 11.6V at key ON to the Blue input to the master switch. Red and Green/Yellow go from the switch to the window regulator, and they are showing the same 11.6V (Red is 11.6V up and 0V down, G/Y is 0V up and 11.6V down). So, the door jamb wiring and master switch appear to be okay.

The only thing in between the switch and regulator I didn't verify is the 2-wire connector clipped in behind the vapor barrier, as I can't find where I put my back probe set... But, that's pretty unlikely to be bad, as it's the pigtail on the regulator itself, which was replaced. Odds are low that both regulators' pigtails were bad.

There's the old thread on fixing the regulator's plastic piece in the track, but that's likely not applicable, either. The only thing I can think of at this point is something in the window rails causing a huge amount of resistance. Any ideas?

 

I'm not quite ready to call it a solution, but it's definitely an improvement: I loosened the bolts for the front and rear window tracks, and in so doing was reminded that I never could do anything with the bottom rear one, as a previous owner had badly stripped it. (Probably used a #2 Phillips instead of the proper #3 bit.) And, of course, it's the one in the recessed hole... So, I drilled it out and extracted it, and replaced it with a new bolt from my bag of spare parts.

I left all the bolts a little more than finger tight, thinking the window's movement might straighten the tracks out if they were misaligned. Having done that, the window goes down at medium speed now. Not great, but not terrible, either. (It goes up a bit faster, but not enough of a difference to make me think there's definitely still a problem.) With the engine running and better than 11.6V to the switch, maybe that will improve to full speed.

I think I'll run it up and down a few times while tightening down the bolts, and hopefully that will retain alignment.

 

maybe I missed this part but couldn’t the window motor be going bad? getting worse when humidity or heat swells the rubber of the window channels

I’ve replaced my sc window motors and regulators at same time when mine got stuck or slowed to a crawl like that so I never knew if it was regulator or motor. Alls I know is it fixed em!
Used oem stuff off facebook 3 different times (on two different SCs) and no problems for 8 years if memory serves.
spraying the channels and parts of the regulator with that window track dry lube spray helps a little too

 

The motor/regulator is all one piece, so I eliminated that as a possibility by swapping in a replacement. Odds are quite slim of both behaving exactly the same. (Pretty sure I also tested it by straight battery power in both directions before installing.) Also, it's cold weather that makes it worse, not heat and humidity.

I've tried lubing the tracks a few times, and that didn't help. Oh, and I also tried a different master window switch, on the off chance that spraying the contacts with electronic cleaners wasn't sufficient.

With the rear track realigned, it's working reasonably well now. Still too much resistance for the one-touch down to work, but at least it goes down nearly as fast as the passenger side.

 

got it. It sounded like you were doing a complicated and careful version of everything but I mentioned motor just in case. For one of my windows I just replaced the regulator with a new aftermarket brand. The other 2 repairs I got oem used off old SCs, semi-tested, and got lucky they worked. Seems you at the limit of what you can do and I hope your solution keeps working for you. Cheers!

 

The above improvement wasn't nearly as much as I had hoped for, but I was standing at an odd angle behind the car last week and noticed something for the first time: the dr's door glass had a pretty big gap along the rearward edge, between it and the outer trim/felt guide, as if it was bowed out in the middle. Either the glass or surrounding piece(s) was warped. So, I swapped in [used] spare glass and outer pieces, plus the spare window rails since the rear one's curve was visibly different from my current one. After getting it all buttoned back up, the window goes down lickety split now!

The original outer trim was starting to lose the black finish on the vertical portion, so it was also worth swapping in the better one. Unfortunately, several of the tiny little screw bosses that hold the outer felt guide to the outer trim broke off, so that may not be a long-term solution.

I ended up with two tiny little screws left over, and can't remember what hugely important thing they were for... It's not the two that go on the inside of the aforementioned vertical black portion (behind the two little plug covers); these ones are much smaller than those. Anyone do window work recently and remember where they go?

While working on that, it occurred to me how much easier door maintenance would be if car manufacturers made the inner skin of the door frame be removable. Just bolt it to the outer skin instead of it being formed as one piece. Imagine just setting the glass into the rails, then bolting the inner skin back on and lining up the regulator with the glass. That would save half a day of frustration, trying to figure how to angle the various pieces in and out through the window frame.

Frameless windows would be another way of making life easier, I suppose. You don't see those too often, probably because it's harder to get them to seal the water out.