Diagnose my clutch over the internet
 

I know I can't get a definitive answer on this without having someone who knows what they're doing "get in there," but I have to try and at least guess what's going on in order to know how and who I want to handle this.

For a few months now, though I've experienced no slipping per se, I've been concerned something with my 1M's clutch has just not been "right."

It was somewhat worse in the cold weather, so I thought maybe I was imagining things, but now I know I'm not.

The most noticeable manifestation of the problem is when starting from a stop in 1st. As I engage the clutch and lift the pedal through the bite point, there's often (though not always) a good bit of "judder" for lack of a better term -- it almost feels as if it's not two parallel planes coming together. Then, almost every time, there's a delay from when I've come up fully through the bite point and when the whole mechanism feels as if it has locked... at which point there's a delayed (not super harsh, but present) "thud" as the whole system is finally working together properly. I have not had any problems or signs of unusual behavior on any other shifts -- only when launching.

It's a lot like complaints I've read online about the so-called "CDV," but these symptoms are not inherent to the design of the car... I had none of these issues for the first 70,000 miles I've driven this thing.

I also don't think it's just routine clutch wear, or a result of abuse -- I'm really pretty gentle with my clutch. I've had several manual trans cars well over 100,000 miles and have never had any clutch issues at all, let alone having to replace one.

The working theory I'm leaning toward is a problem/failure with the dual mass flywheel springs. Do those of you more knowledgable than me think that's a viable theory? Could one or more springs be shot, and the "thud" I'm feeling be when one of the independently rotating pieces of the flywheel hits the physical stops built into the other half?

I want this fixed, but want it done right. I have what I think is a good indie guy, but don't know if I should take the leap to have him do this, or go pay the exorbitant rates to a dealership service department where I know it will be done "by the book."

Any insight or advice appreciated. Thanks!

Yes, it sounds like a dual mass issue.

Thanks!

Isn't a clutch and flywheel within the abilities of a decent indie guy?

Also, who is your decent indie guy? I don't really have one up here.

I guess, I'm just a little paranoid. I don't want this to turn into a multi-phase nightmare.

I use this guy: http://www.pinnaclemotorworks.com

I've only used him for routine maintenance stuff so far. But he seems to know what he's doing, doesn't try to sell me services I don't need (unlike every fucking dealership service dept), has been in business a long time, and has a lot of long-term customers with multiple BMWs, MBs, Porsches, and Audis. :dunno:

Damn I had never heard of Stirling NJ. And I went to grad school in New Brunswick. :lol:

That stinks about the clutch issues though. :(

JV said the flywheel that came out of my E46 was in pretty good condition. You can have that one if you want it. :D

So... I take that comment back. The springs on it are shot.

Still might be better than Plaz's. :lol:

I did notice that my clutch would shudder sometimes, usually in reverse. I assumed that was more about the surface of the clutch plate though.

I'd be curious to see when I come get the car, if you haven't tossed it already.

My general recommendation is give it an extra 500 revs before engagement. Any solution involves a new clutch assembly, so who cares if you use it up a little faster?

Edit: And I agree that it's most likely that the flywheel is failing to operate correctly. Stupid dial mass crap.

I have all the parts, I don't think I threw anything away except old gaskets

Right, thanks, that's what I've been doing most of the time, almost subconsciously. And being more judicious in stop-and-go traffic to avoid as much as possible situations that will require extended slipping rather than full engagement immediately.

Kind of maddeningly, this morning it showed no symptoms at all, behaving perfectly without any special treatment. Not sure how that happens -- either it's broken or it's not, right? :dunno:

There might be some uneven clutch material deposits on either the pressure plate or the flywheel which could cause the juddering, which could cause the two flywheel masses to get out of sync. Just a guess. Clutches also grip better when they're warmed up, so if it was cold this morning, it might hide the problem.

If there's a single-mass solution for your car I'd probably choose to replace the clutch / FW with that, assuming you take the car in to get the clutch done. There is nothing magic about BMW clutches that requires any specialized labor. Any good indie shop should be able to handle it. It'll be expensive, though.

That's an interesting thought (deposits). It was cold this morning, but the problem was pretty horrific at times over the winter, too. I wonder if doing some gratuitous clutch burning would help "mill" any such deposits off, or just make the problem worse.

Single mass is also an interesting thought, though with this car I'm especially hesitant to do anything not to OEM spec. I'm going to sell it at some point (not soon), and I have a feeling potential buyers for a high mileage 1M are going to be extra anal-retentive about absolutely everything. Even moreso if it goes up on BaT. (Have they even had a 1M yet?)

Good to know there's no special BMW clutch juice required. Thanks.

This is why I complain so much about too tall gearing.

I can't comment on what could be the issue but in regards to using a dealership for replacement versus a shop I wanted to give you an issue I went through.

When I had that NSX a few years ago I had a shudder on the clutch at take off first gear as well and had the dealership replace the clutch which I paid for. The replacement clutch was if I recall a little better but had a shudder at take off as well ... the best part of having an Acura dealer do the work is there was a warranty and they ended up replacing the clutch again without any argument or questions. They also did multiple adjustments to it when I wasn't satisfied with the feel. Another benefit is they supplied a loaner car each time I took it in.

I don't know if a regular shop would have done this or not but I do know the dealerships never minds doing warranty work if there is an issue with their work being they get paid by the manufacturer.

Sure, but I'm well out of warranty. And my guy does have loaners. (A couple of E46 325s)

IIRC, dealerships also charge roughly twice as much for the job. The point that the dealer work/new parts are covered by some level of warranty is valid, though.

The Mini has started doing this too. I have also started bumping up the revs at launch to try to avoid this. Guess I'm getting a new clutch soon.

:confused:

IMHO any Indie shop that stand behind their work isn't going to last long.

Edit: and Plaz already has a relationship with his shop in Sterling

Or not. If you can live with / drive around the juddering, you could have tons of life left in the clutch. The dual mass springs seem to wear out a long time before the clutch disc itself does most of the time.

Yeah, it is more annoying than anything else. It's still perfectly functional, and if that is the problem, I'm less concerned that it's an omen of imminent failure.

Sounds good ... but keep in mind my car was a 1995 NSX and way out of warranty ... the work was done in 2014 or maybe 2013 and I paid for the original clutch to be replaced but once they did the work it was warrantied ... in other words I paid for the clutch but once they did the work the work itself was warranted for 12 months if I remember correctly whatever was wrong was covered under the warranty

I shudder all day at work. Oh, that probably doesn't help.

Yeah, I was misunderstanding the warranty thing, you guys were saying the work is warranteed (sp?). I get what you're saying now. I'm not sure what route I'll take yet.

You might have some deposits of foreign material that need to be burned off too.

That sounds racist.

Actually, I think this may have been the issue. A few days ago I did an intentional controlled clutch burn (was painful, felt very wrong to be doing that). But since I did it, I haven't felt the symptoms again. Time will tell, I guess.

You should have just taught your daughter to drive stick. :lol:

Glad it helped!!!

:lol:

Think it's fixed for real?

It hasn't been long enough that I don't think about it when launching anymore, but I haven't felt the symptoms.

When I forget about it then I'll know it's fixed. :lol:

So that fixed it, then it recurred, I did the "controlled burn" again, and it fixed it again.

I'm thinking it's probably just buying me time. Until I burn away the remaining clutch material, or the DMF completely fails. Maybe it has multiple springs and one of them is shot, so it's more sensitive to material deposits?

I don't know. Just going to tread water with this repeating cycle until I'm forced to actually deal with it, I guess.

Ugh, that's slightly disconcerting.

What's disconcerting? That your car is going to kicked out of its home away from home soon to make room for new blood?

:lol:

:eeps:

This problem has disappeared. :dunno:

That is great news !