Mystery problem with clutch. HELP!

Okay, I’ve got a '93 Acura Integra with a 5-speed transmission. The car has about 150,000 miles on it and is in relatively good shape, mechanically. It was owned by a foreign car mechanic who gave it to me when he bought a new car. He’s been maintaining it all along.

About 5 months ago, I loaned the car to the wife. When she returned it, I immediately noticed that the clutch wasn’t fully disengaging the engine from the transmission, making shifting difficult but not impossible. The problem got worse, to the point where I’d have to drive as if it had no clutch at all, even turning it off at a stop street and starting it in first gear when I was clear to move. Some days were worse than others, however, which I found puzzling.

The mechanic, Jake, and I decided it might be the clutch cable. Perhaps it had developed a kink, and sometimes the kink was kinkier than other times. So, he replaced it with a new cable, but that didn’t change anything.

What’s weird is that some days, the clutch is fine. It works exactly like a clutch is supposed to work: you push in the pedal and the engine disengages completely from the transmission. Other days it’ll be working properly, then suddenly stop working properly. Some days, I’ll drive home from work with the clutch okay, park the car overnight, and when I start up the next day to drive to work again, the clutch will already be in “not working” mode, requiring that I shift at certain RPM points all the way to work.

The clutch itself is good, i.e., it doesn’t slip at all. Also, to replace the clutch will cost me around $700 here on Nantucket Island from the shop where my friend works. The Integra is good transportation, but it’s exterior is kind of rough, with dents, rust patches, etc. I’d rather not spend that much money on a car that will be hard to sell.

Also, I don’t know if replacing the clutch will solve the problem because—I don’t know what the problem really is. How could a mechanism be okay one day, not okay the next?

Look under the dash at the bracket that the clutch cable is attached to. While watching the bracket, operate the clutch pedal by hand. If you see the bracket flex at all while operating the clutch pedal the bracket is cracked. When this happens, the entire clutch cable assembly moves to where the center cable doesn’t fully disengage the clutch. When I’ve run into this problem I just get under there and weld the crack shut.


Thanks, Tester, but that wasn’t it. My mechanic friend Jake and I both took a look at it today and the bracket is sound. It doesn’t move at all---- no flex. Any other ideas? Anybody??

Examine the other end for the same issue.

If that turns up nothing then it’s most likely something internal to the clutch. You’d have to tear into the clutch to diagnose this and, once you do that, you’ve paid for a clutch job anyway. Might as well do it with new parts rather than reusing the old.

I understand the reluctance to believe that the clutch could work very well one day and almost fail the next, but the clutch is probably the problem. In general, if the clutch does not feel easy to engage and disengage at any point, you have a very worn clutch plate.
Just because the system will limp on as long as possible does not mean everything’s okay. How’s your gas mileage?

Tomorrow, I’ll inspect the other end of where that cable goes and check it. Maybe the other bracket is somehow loose: when it’s in its proper position, the clutch disengages properly, but if it can move to a different position, the clutch cable is unable to pull far enough to disengage the engine completely. That might explain what’s going on with it.

The way I was taught to check for wear in a clutch is: driving along in 4th gear, you push in the clutch, raise the RPMs pretty high, then quickly release the clutch pedal. If there’s a sort of “jolt” when you do that, the clutch still has plenty of life. If there’s a slow, smooth transition, it indicates that the clutch plate is worn.

I’ve used that method a few times, and there’s never any indication that the clutch plate is worn. We may yet find that there’s a problem with the mechanical components in the clutch, but the plate is probably okay. (Whether it is or not, if I do a clutch job after all, I’ll replace it.)

But I can tell you, when the clutch is in “okay” mode, it really is okay! It disengages the engine without any sign whatsoever that it might be worn. And when it goes into “not okay” mode, it’s a sudden transition. One second the clutch feels fine, the next, it’s almost non-existent.

Theorizing here for a minute and with not much familiarity off the top of my head as to how this is set up let me pose this possibility.

The transmission has a protruding soft aluminum nose for the throwout bearing to ride on.
The throwout bearing has a grease groove on the inside that is machined when new. Grease is packed into this groove and this lubes the nose that the bearing rides on.
With age, wear, and hardened grease, sometimes the bearing tilts a tiny bit and the edge of the grease groove, which has knife sharp edges due to the machining process, may dig into the soft aluminum nose of the transmission. This can be erratic in nature and cause a fine one minute, goofy the next situation.

Subarus had a problem with that at times although theirs was slightly different in that the bearing mounts on a sleeve and I think the Acura does not. Same principle though.
Every time I performed a clutch job on a Subaru I always put the sleeve on the lathe and cut those sharp edges off followed by packing it with fresh grease.

I’m not saying this is the problem; only that it’s a possibility. If you drop by a parts house and look at a throwout bearing for this car you may see a groove on the inside. This will be what I’m referring to. Bad part is that there is no way of knowing short of tearing it all apart. Hope that helps anyway.

(As to those grooves, I’ve sliced myself a few times. That’s how sharp they are.)

Easier on the car just to put it in 3rd gear at about 15 mph and floor it. If the RPMs rise appropriately to the car’s increase in speed, you’re good to go. If they rise quickly but the car doesn’t speed up, you know your clutch is slipping. This method avoids premature wear on the clutch, which is what happens when you dump it after revving high.

As the husband of a wife and the father of two daughters and a veteran of many mysterious mechanical problems, I tend to focus on the fact that this first occurred after your wife used the car.

Was it, by any chance, raining that day, or could she have driven anywhere near seawater?

A rusty splined shaft can cause the problems you are experiencing, and water in the clutch cavity can lead to a rusty splined shaft if the grease is no longer protecting it.

Now, that sounds like it might well be what’s happening here, and would explain the intermittent nature of the problem. I guess there’s nothing for it but to have the mechanic tear the whole thing down, put in a new clutch, and inspect the throwout bearing. If it looks funky, he’ll either dress it on the lathe or replace it.

I’ll pop back in here on this thread and let everybody know what happened. Thank you all so much for chiming in with your suggestions and help. I really appreciate it.

Aha! Well, that might well be a factor. I live on Nantucket Island, and my car is constantly going through deep puddles, occasionally puddles with salt water in them. That’ll be another thing to check when it’s disassembled. Thank you!!!

I sure hate the thought of tearing something apart without being at least 98% sure the problem inside the clutch assembly. That’s about the only thing I can come up with seeing as how the cable is good, the underdash bracket is good, etc, and Manolito also has a good point about the splines.