Every time I go to put down my (power) window after being fully closed, it
makes a big "bang" and then rolls down fine. Any suggestions?

Re. 1
Your window can be adjusted internally which amy help. also getting in the door and lubricating can also help. i recently had to replace the control unit since the cable broke. you may be looking at one yourself. http://www.nissanparts.com had the best price on it.

Herb Jabs

Re. 2
Remove the door panel and check out what the linkage is doing. with the window half down, can you "wiggle" it back-and-forth or side-to-side? Could be an adjustment or something broken in there. Not sure if this is any help, but it is a suggestion!

Jason
'90 240SX

Re. 3
Sounds like the window is out of alignment or something. I had to replace my whole rack assembly in my driver's side door last summer. $150 from Nissan without the motor! It was a bitch and a half to do also. I had to take the whole window out to get the damn thing out. There is a few plastic gears on this assembly and one of mine stripped and broke causing the window to drop down and it wouldn't come back up. Maybe you might have a tooth missing on one of those gears and its just jumping from one tooth to another where the missing one is. Better see a dentist for that! hehehe

Kris -- 1990 240SX

Re. 4
Take the door panel off and see what's loose. that's all it is usually, i had the same problem with my Z.

John

Re. 5
Is the glass seating properly? Is the door hard to close with the window up sometimes? After my car got broken into by someone who apparently slipped a coathanger between the glass and weatherstripping, the glass was misaligned enough so that the top edge of the glass gets hung up on the top edge of the door opening occasionally. It sounds more like a "thud" when it pops itself back into place...

-mike

Re. 6
Sounds like one or both of the rubber stoppers are missing....

Ken
'90 240sx

Re. 7
On the 89 I've got, I had to replace the complete window riser assembly on the drivers side door a month or so ago. After getting the thing dissassembled and removed, installing the new one wasn't as bad as I expected. A Nissan specialist instructed thusly:  When you drop the assembly in place and get all the bolts installed, the four in the bottom and the two at the top (primary adjustment, if I remember) get in the car with your socket, ratchet and extension, roll up the window (mine was electric, so the switches had to be removed from the door panel and plugged in temporarily to the harness). Watch it go up, stop as it nears the top and then slowly bump the switch to get it to the top without pushing it too high. Apparently the window motor has a torque limiting switch inside instead of a syncronized switch, thank goodness. When I ran the window up, and it seated in the frame of the roof snugly, I  tightened everything down, got out of the car and inspected the fit. Take a dollar bill and close the door on it all around the window to see if it's snug, and not overly crushing the rubber. This would make the door bind on the glass as you closed it- the pressure on the glass ain't a good thing. I did this a couple of times to see if it was sealing properly- it was, so back together it went. No leaks, no wind noise etc. Got rid of the rattle that was coming from the riser assembly that was about to fail (and then the cable broke). Don't know if your experience would have benefited from this or not, Price. Was easier than I thought it would be tho.

Dave
89 240SX 145K
[email protected]

Solution:

I had the same problem when I first bought my car. One day while I was changing the speakers in my door I decided to see what the problem was. It seems that the screw that is used to screw down the door handle latch and lock  combo is too long. What you are hearing is the window going down and being stopped by the screw, and then pushing past it causing the banging sound. The solution is very simple. All I did was take the screw out and put in a couple of washers (3-4) to increase the space between the screw and the window and close it back up. Before you  put the door panel back on, test the window and make sure it goes down smoothly. Problem solved!

Allen Eshmoili
Email: [email protected]

Another Solution:

(Re 1990 Nissan 240 SX HB)  Investigated the driver's side window when it suddenly dropped with a "bang" into the down position.  Took the door panel off, manually lifted the window up and tied/blocked it temporarily in place.  Called several Nissan dealerships for a "feel of the problem."  Went to the library.  None of the Nissan books assisted with info re taking the "regulator (the window track & pulley system)" out.  Used good judgment and common sense.   Undo simple wiring and bolts.  With the window in the up position, you can wiggle the system out.  It's easier if you take the plastic molding strip off the top of the door.  Gives you and extra quarter inch of space.  The cable had broke on the regulator.  Went to a bicycle shop and bought a thin brake cable for a fix.  Forget it!  You must purchase the whole thing.   The regulator w/o the motor is $149 at Nissan parts (Cincinnati, OH area).  I found a regulator w/motor at an upscale junk yard for $125.  It was off a 1992 Nissan SX and was a perfect match even though my car was manufactured in 9/89. Nissan changed the part number about 2/90, but the regulator is "identical."  Nissan dealership wanted $110 to install plus the part cost.  It's a relatively easy job with only a socket set and minimal tools required.  Fortunately, I now have an extra motor should either side door motor go bad.  Incidentally, the motor alone costs new about $280...unbelievable!

Dennis
[email protected]