What's That Popping Noise? ...or... Why Did My Window Fall Into The Door?

Service Bulletin Alert

See Technical Service Bulletin (TSB) #93-004 - "Popping Noise from Window Regulator"

The bulletin for the window regulator "POP" was issued on March 9, 1993 and includes the 1991, 1992, 1993 model years. In this bulletin it states to check the regulator for the new updated parts. If the regulator has not been updated then replace the regulator instead of just applying grease for the pop noise. While the bulletin specifies 1993, it seems that at least some 1992 cars received an updated version of the regulator which fixes the issue with the regulators breaking.

TSB 93-004 describes two different window regulator problems that apply to 91-93 NSX's:

1. The more minor one is that a white plastic spool that supports the window needs to be lubricated. Lack of appropriate lubrication causes the spool to bind and make a popping noise while the window is raised or lowered. My presumption is that this binding then under the right circumstances strains the lift cable and leads to the more serious problem below.

2. The more serious problem is that old-style window regulators has a flimsy attachment of the cable to the spool. New-style ones have a reinforced ("boxed") attachment. Old-style ones would break that attachment, leaving (or dropping) the window in a down position. The only fix for this is to replace the entire regulator (an elaborate assembly of motor, flexible drive cables, a track for the spool to ride up and down in, etc.) with the new-style one with the stronger cable attachment point. The part numbers for the replacement units are:

Left: 72250-SL0-A02
Right: 72210-SL0-A02.

These parts list for $300-$400 each. Labor to replace each one is about one hour.

[HS] This is possibly the most common (and expensive) failure in the early cars. In 1991 and some 1992 cars the question is not "if" the window regulator will fail, just "when." It's a design flaw, pure and simple.

You might be able to get it fixed for free if you (1) have a friendly dealer that will admit it's a product problem, or (2) if you hold your breath until you turn blue, or (3) were smart enough to buy an extended warrantee.

I did the latter. Both regulators.

[KJ] Applying stress with the windows partially open is bad, as the "in-between" position puts most/all of the the strain on the regulator linkages. i.e., driving fast with them cracked open, or slamming the door, or resting your arm on them.

While You're In There, Lube It Up

You should lubricate the regulator and window guide tracks periodically. If you're going to take your door apart for some reason it's a quick and easy thing to do while you're in there. From Service Bulletin, 93-004 "Use High Temp Urea Grease part # 08798-9002 all around the white plastic  spool and on both sides of the glass mounting plate."

[JST - 99/5/13] When I bought my '92 NSX a couple of months ago, the driver's side window slowed as it raised. Since I enter a parking garage with a card every day and have to roll the window down and up, I was concerned. I asked the dealer about it and was told the problem could be fixed with an adjustment and lubrication.

$196.00 later the window worked like a charm and has ever since. They completely remove the window, clean and lubricate all the parts, then reassemble and adjust. The window is actually a little higher fully closed than it was, making a better seal. I'm very pleased with the work. (was also glad to find out my driver's door already had the newer window regulator!)

This service is described in one of the service bulletins. It also stops the popping noise you may hear when raising the window.

Background Info & Replacing Entire Regulator Assembly

[KP] Just to qualify my statements, this evening I successfully replaced my window regulator assembly with a "used" assembly that a friend of a friend found for me. The replacement part came from a '95.

To those complaining about the poor engineering by Honda and their lack of accepting responsibility... I say you're all wrong. First, if you look at all of the engineering that went into this car and all of the subsystem that were really designed from scratch - especially those dealing with all of the aluminum, it's not fair to critique such a relatively minor point as the window regulator. BFD!

Second, I think Honda stepped up to the plate as soon as the problem was discovered and goodwilled most of the failures. You should all be aware that they issued a TSB describing the situation. In fact, on my '91 - an 8 year old car, Honda was willing to goodwill the part but not the labor. Furthermore, Honda re-engineered the part (in '93 I believe) and to the best of my knowledge there's been no issue with the new regulators. In contrast, I have a couple of friends with Nissan Maximas and they go through regulators like I go through tires! So, IMO, it's real hard to find fault with Honda's action regarding the regulator and their continued gestures to satisfy owners.

Second subject: What is it and what fails? This topic is necessary because most of the discussion has been dead wrong regarding the failure point. Contrary to what you've read here recently, the culprit is NOT that little piece of plastic. In fact, the new part has that SAME piece of plastic. Read on.

OK, for the door-panel-removal virgins, the window regulator assembly consists of a motor with two cables protruding from it. One of these cables goes up and over a pully inside the door panel and DOWN to widget that bolts to the bottom of the widow. Similarly, the second cable goes down around a pulley and UP to this same widget that's bolted to the window. This widget that bolts to the window slides up and down in an aluminum guide which is the final part of the regulator assembly. Can you picture it? So, when you press the window up button, the motor turns simultaneosly winding the top cable in (pulling the window up) and letting the bottom cable out (to allow the movement of the window).

Conversly, with the down button, the motor turns the opposite direction winding the bottom cable in while simultaneosly lengthening the top cable allowing the window to move. This assembly moves up and down via the guide bar. To replace the window regulator assembly you simply unbolt the window from this widget (2 -10mm bolts), unbolt the motor (3-10mm bolts), and unbolt the four 10mm bolts holding the guide in place. Once free, the entire assembly is easily removed from the door well.

The infamous regulator failure occurs at the widget (I don't know what else to call it) where the two cables meet. Each cable is terminated in a small cylindrical barrel. Now, imagine that the widget is a stamped piece of metal (It's really cast, but go with me on this.). Imagine cutting an H in the metal and then bending the tabs (on either side of the horizintal crossbar of the H) 90 degrees toward you. The result is that you have a rectangular *hole* framed by two tabs. Now there's a plastic piece that slides into this rectangular *hole* and is held in place by the tabs. (Have I lost everyone yet? If so, draw an 'H' about 1" high on a piece of scratch paper, cut on these lines, and bend the two flaps toward you and you've basically got a model of what I'm talking about.)

Now, you cut a narrow but deep V in each of the tabs (uh, weakening them... hint, hint). The cable itself sits in the V and the barrel of the cable sits in the little plastic block sitting in the square hole between the tabs. Similarly, the other cable sits in the other V and its barrel sits in the same plastic block. Now, when you move the window up and down, the cables are playing a tug-of-war on this little plastic piece. But remember, this plastic piece is framed by these two tabs to kind of protect it. But, I also said that these two tabs had these V's cut in them to allow for the cable. The failure IMO, (I stress, IMO) is that the pulling by these cables against the plastic in turn puts pressure against these tabs. Gradually, these tabs begin to bend outward.

With time, these tabs become bent enough that they are no longer suppling the needed support for the plastic piece which locates the cable ends. Contrary to the design intent, the plastic piece is now trying to withstand the tug-of-war force from the cables all by himself. Snap, Crackle, Pop and Thud goes the window.

As I said earlier, this plastic piece is identical in the new design (at least as far as I could tell). However, the widget piece is what's been re-engineered. The square *hole* is no longer framed by just these two tabs. The new piece is now framed on all four sides. (Remember, it's a cast piece so these sides are all joined together.) With this design, there's no tabs that can bend with time (usage). The plastic piece is the same but he's never asked to endure the pull of the cables.

So, for those of you looking for new plastic/aluminum/titanium inserts... you might get lucky and come upon a design that works. If you do, I'll be at the head of the line because I want to take a proactive step before the driver's door let go. But, be concerned with these tabs and how the real point of failure should be addressed. Bending these tabs back into place is NOT an option. Since they're cast and not stamped, they'll certainly break off. Also, any *obvious* design alternatives for the plastic piece will continue to bend these tabs and they will eventually break.

To address Brian's comment about his windows being slow, you probably need the "real" fix which includes a new assembly (and motor).

[KP - 98/12/26] It seems that the window regulator problems will continue to plague the members of this list until we have completely eradicated the problem by replacing them with the newer designed part. A couple of questions have appeared on the list and at least one person has privated me (that sounds objectionable), so if you'll indulge me, I'd like to state my opinion on these issues.

The first questions ask if the slow roll-up speed is a precursor to the regulator failure. Well, yes and no. The failure seems to be a stress related. If your window is slow, it would seem that more stress is being placed on the part that breaks. Someone posted some good advice to get in their and lube thing up a bit. I'd recommend this and add that if you have the "old" regulator design, you should just go ahead and replace it at this same time. This will save you the aggravation of having a failure at an inopportune time. (Such as when you are 200 miles from home with your spouse in the car. We call this a Gowardism. Not recommended.)

Another question asked if you could expect a longer life for the pass window since its usage is maybe 1/5 of the drivers window. Logical question, but on both my car and Dave's, the pass window was the one that failed first! A pure guess on my part was that the auto down may help to protect the driver's window from the stresses that a pass could inflict by holding the down button down for a few seconds after the window was all the way down. Since I've never (yet) had my driver's panel off, I can't be sure if the drivers regulator is stock. I purchased the car with 8K miles so I doubt if it has been replaced, though I could be wrong.

The final question is if someone could do this on their own. My view is that this is a straightforward repair that can be done at home. One of the hardest parts (though not THAT difficult) is getting the door panel off. Just take your time and use the manual which is very good at describing the steps. Roughly, the steps are:

1. Pull the door panel (per the manual.)
2. Pull off the speaker enclosure - to get it out of the way.
3. Carefully (without ripping) pull back the plastic liner. Peel from the outer edge back toward the hinged side of the door. About half way will do and just stick it on itself so it stays out of the way.
4. With one hand, lift up the window so you can reach in the big hole and undo (1 of 2)10mm bolts from the window.
5. Position window (up and down) to stick an extension in the small 1.5" hole and get at second 10mm bolt.
6. Lift the window all the way up and put a strip of 2" x length of window masking tape along outside edge of window and body. This will hold the window up out of your way.
7. Take off the (4) 10mm bolts holding the regulator "guide bar" in place. (I marked them first to get them back to the same position.)
8. Undo plastic clip that hold cables up.
9. Loosen 3 10mm bolts holding motor.
10. Remove assembly.
11. Install is reverse of these steps.

Replacement Regulator Warning

[JGR - 99/2/10] I purchased a replacement window regulator in January of 1999, using the part number from the FAQ and Acura Service Bulletin 93-004. (Right door: 72210-SL0-A02). This part had the OLD STYLE cable holder, not the new style, teaching us that just because you are ordering a new part these days, you cannot assume that it has the new design configuration. Before you install or allow your mechanic to install a replacement regulator, it is HIGHLY RECOMMENDED that you personally inspect the cable holder portion of the mechanism to insure that it is the NEW STYLE, since some regulators with old style cable holders have shown up, and some dealer mechanics may not be familiar with the difference.

Dali Racing's Replacement Regulator Clip

[MJ] I finally got the window regulator fix-its thingy done. They are a 6061 aluminum replacement for the plastic part of the window mechanism that breaks and causes the window to fall down on a cold and/or rainy night miles from home.

These units are so strong that even if the part that failed first (the pot metal holder for the plastic part that retains the actuator wire) is completely broken off, it does not matter and the window will function perfectly.

IMO they are highly cost effective option ($18.20/pair includes Priority Mail shipping) over replacing your entire unit like Acura wants you to do for 'only' $911.10/the pair (Acura list). Stick a set in the glove box to install the next time you lube your window track - you DO lube your window track every so often - right?

[MJ - 99/5/21] After installing a couple of window fix-its thingy clips today; (in window regulators that were out of the car) all I can say is "I'm glad I ate my Wheaties today". Trying to stretch the steel cable is a bitch. It took two of us, 1 to compress the springs under the little rubber bellows booties at the ends of the cable next to the motor, and 1 to stretch the cable end into the aluminum piece. That said, I'm not to sure that it can be done too easily with the unit mounted in the car.

The NSX Service Manual on pages 20-6 to 20-13 (1992 manual) shows how to disassemble the door and remove the window regulator. I think when you get in there you will get all greasy too. Make sure that you get some good synthetic grease (there was yellow stuff in my sample regulators) so that you can clean and re-lube the tracks, and all the plastic cable guides etc. The manual shows you where to do it. I will enclose Xerox's of the pertinent manual pages with all regulator orders. A nice pair of long nose pliers is very helpful for stretching the cable into place.

[WL - 99/5/21] I checked with my dealer here in Las Vegas about installing those little "thingies" and he said it would cost $130.00 per window to remove the regulator, install the thingies, and grease everything properly. from the sounds of Mark's post I think I will let them do it. Still a lot better than new regulators.

[JRW - 99/9/6] This weekend I decided not to risk taking any more chances with my window regulators and under took the job of replacing the plastic "thingies" with the metal ones from Dali Racing. I thought it might be helpful to any one considering the same thing if I posted some comments about my experience.

First, I was pleasantly surprised to see that the one on the drives side had already been replaced. Thanks to Mark for putting something in the instructions about differentiating between the old and new models. I then went after the passenger side and found the old style -- and the metal tabs were bent, so it looks like I got to that one just in time. I managed to get it changed but had to put the door panel on a couple of times before I remembered to do everything (get the plugs sticking through the right holes in the plastic, etc.).

There are a few things to make it easier. First, the instructions are from the manual and include everything about taking everything apart. NOTE: you do not have to take off the front and rear glass guides. Fortunately, I figured that out before I did it. The problem is that if you remove those, you have to realign the glass and that could be a real pain, plus it takes a lot more time. You also do not have to remove the latch assembly, lock cylinder, inside crank, stopper plates, or the lower door weather strip (the latter can be pulled out enough to get to the seven door panel screws. You do have to remove the regulator mechanism and (including the motor). Also, I was able to do all of it myself, although it was tough getting the cable extended enough to get both ends in the thingy.

The biggest mistake that I made was to start on the passenger side before I put the driver door back together. You have to position the window about four inches up from the bottom so that you can reach a bolt through a small hole--that takes some positioning. Since I had the diver door off, I couldn't roll either window up or down. Therefore, to get it to work, I had to plug in the window connectors and hold the panel up while I turned the ignition key on to work the window. (The driver side has to be hooked up even to work the other side. ) Fortunately, no one was watching while I did this several times.

Finally, the instructions say to use a high temp. urea grease. i looked all over (NAPA, etc.) but couldn't find it. Finally, I got a brain storm and called my local Honda parts department (I'm not lucky enough to have a nearby Acura dealer). They had it--it's expensive (about $11).

I have to roll my window down a couple of times a day and I was getting a bit antsy worrying about it, especially since I had heard that if it breaks, it may mean the whole regulator would have to be replaced. Plus, since I had been nagging Mark to manufacture the thingies, and since I bought them from him, if the regulator broke before I got it fixed I knew I would freak.

In summary, the part works, and you don't have to take of as many of the parts as the instructions state. And, although I'm not going to tell you how long it took me to do it, I'm feeling much better today.

[EK - 99/8/14] My shop (not dealer) charged me $175 to install the Dali Racing clip, straighten the cable and rewound it on the spool and $105 (1.5 hrs of labor) to install the clip on the passenger side (which didn't fail).

[SHO - 99/8/9] Please do yourself a big favor. If you have a 1991 or 1992(some) car, buy a set of Dali fix BEFORE that thing snaps. I was up all night helping a fellow NSXer fixing it. It just snapped while he was driving. Boy, when the plastic clip breaks and cable flying, there are additional damages too.

When we tried to replace the broken plastic clip with the Dali piece, we found that the one metal prong holding the clip was broken. Also the cables no longer meet the new clip. It was 2 inches too short no matter what we did. We tried brute force, playing with the window motor, prayed, swore (a lot), and danced while swearing. A desperate call to Joon Lee (thanks, Joon) revealed that when the 2 cables lose tension due to the snap, the cable inside the motor assembly goes
out of track. This results in kinking of the cable, overlapping, and sometime jamming. So we opened up the motor/spool. There was a spring like the ones in automatic watches that swung out and hits your face if you are not careful, two-piece spools that were impossible to pull out without damaging them, and loads of grease.

There it was. A cable that was kinked, flattened, and totally off track. We spent the next 3 hours just trying to fix the SHAPE of the cable so that it fits the grooves of the spools again and then through numerous fine adjustments to find the exact mating point of the 2 spool halves so that that was enough gives for the 2 cables end to meet at the new Dali clip.

The next thing to do was the damn spring. There were 18 revolutions but the best we could do was 16 before the damn thing snapped right out. So now we ended up with a broken prong, a kinked cable, a damaged plastic spool, a partially wound spring, and a less than perfect motor mechanism. We are still afraid that this motor/spool will eventually fails. Then we finally put the regulator back on the car and the operation was quite flawed with the top 2 inches of travel clicking.

From this experience, I think if it snaps, just buy a new regulator to ensure proper future operation and spare all the frustrations. But if you want to save some money and end up with a properly working regulator, do it before it snaps. If you do change the clip, make sure that the 2 cables maintain proper tensions at all time while being transferred to the Dali piece to avoid going off track inside the spool. Remember the motor/spool is not serviceable. We were just separate to pry it open.

My friend changed the other side the next day before it snaps. The entire job was much, much, much easier and the resultant operation ended up being perfect like new. Please, please change the clips NOW.

Easy "Dali Window Fixit Thingy" Install Instructions

See the DIY section Easy Dali Window Fixit Thingy Installation for a quick and easy way to install the Dali Window Fixit Thingies before yours break.

How Long Does It Take For Them To Fail?

It seems to vary a lot. Here is what some owners have reported.

Regulator repair costs

I just had my car into Brookfield Acura for a new left side widow regulator...cost $597

Failure Reported By