1G Fidanza flywheel act clutch issues

[XC92]

I took some additional pix today of the master cylinder rod. The nut's pretty close to the end. With a new clutch and pressure plate and assuming the flywheel step is correct, shouldn't it be a little closer to the MC and not so close to the end? I tried measuring the play and max and min pedal height today but it was getting cold and dark so I'll finish it tomorrow.

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[pauleyman]

Can't remember did you say you had rebuilt the pedal yet? May not matter on a stock setup since you're going to drop it anyway. You can check it again at that point.

 

[We're on Boost]

I took some additional pix today of the master cylinder rod. The nut's pretty close to the end. With a new clutch and pressure plate and assuming the flywheel step is correct, shouldn't it be a little closer to the MC and not so close to the end? I tried measuring the play and max and min pedal height today but it was getting cold and dark so I'll finish it tomorrow.

No that looks about normal actually. I would be pretty confident that you have some pedal free play there.
This is why you find a lot of posts in here about people running out of adjustment on the master rod, and doing various things to have a little more.
On the 1g, there isn't a lot of adjustment available in the first place because the master rod does tend to wind up almost out of the clevis.
Then if you have other stuff going on like a lot of wear (looseness or slop) in the pedal assembly parts, you might run that rod even farther out of the clevis. Especially if you have a heavy springed clutch that also needs a lot of throw, like an ACT 2600 or 2700, so you are then trying to get all the throw you can get.
Take a look at the only post I have in my "build thread" haha. It shows a pic like you took, and you can see that my master rod is even farther out than yours. At the time of this pic, this stuff was just like how ER put it together, I had not changed anything. This is with an ACT 2700 clutch and a new aftermarket disc that is stock thickness (I measured it).
The whole point of the post is to show that English Racing had to weld on a large nut to the face of the clevis to get more adjustment there. Other people have swapped in a longer rod there, from I think a 2g master. Anyway, your position there looks pretty nominal for new stock OEM stuff installed.

Here's a link to my page, go to post #4:
https://www.dsmtuners.com/threads/1990-talon-tsi-english-racing-build-2016.506651/

 

[XC92]

Can't remember did you say you had rebuilt the pedal yet? May not matter on a stock setup since you're going to drop it anyway. You can check it again at that point.

Haven't rebuilt the pedal or adjusted anything there yet. New SBC Stage 2 DD clutch kit, old OEM flywheel, cleaned up and lightly wire brushed but not machined, new slave cylinder with new fluid properly bled (including pushing in the rod several times), stock OEM lines & hoses, stock OEM master cylinder, stock OEM everything under the dash.

And yes, I'm going to have to drop the trans sometime next year, the earlier the better, weather being the main factor. I'm going to give myself up to a month to get it right since it's my first time working on a trans. I'm debating how many miles to put on it till then with the old flywheel that wasn't resurfaced but "looked" ok to my untrained eyes:

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Finally, while I'm at it, I finally got around to fixing that steering joint assembly issue. I loosened the steering column and pinch bolt and wiggled things around till I got a good fit:

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My guess is that when I reinstalled the steering rack and subframe, something was loose in the steering column, either the mounting bolts or pinch bolt, and it pushed things up. But, whatever it was, things are fine on both ends now. Another nagging problem solved!

No that looks about normal actually. I would be pretty confident that you have some pedal free play there.
This is why you find a lot of posts in here about people running out of adjustment on the master rod, and doing various things to have a little more.
On the 1g, there isn't a lot of adjustment available in the first place because the master rod does tend to wind up almost out of the clevis.
Then if you have other stuff going on like a lot of wear (looseness or slop) in the pedal assembly parts, you run that rod even farther out of the clevis. Especially if you have a heavy springed clutch that also needs a lot of throw, like an ACT 2600 or 2700, so you are then trying to get all the throw you can get.
Take a look at the only post I have in my "build thread" haha. It shows a pic like you took, and you can see that my master rod is even farther out than yours. At the time of this pic, this stuff was just like how ER put it together, I had not changed anything. This is with an ACT 2700 clutch and a new aftermarket disc that is stock thickness (I measured it).
The whole point of the post is to show that English Racing had to weld on a large nut to the face of the clevis to get more adjustment there. Other people have swapped in a longer rod there, from I think a 2g master. Anyway, your position there looks pretty nominal for new stock OEM stuff installed.

Here's a link to my post #4:
https://www.dsmtuners.com/threads/1990-talon-tsi-english-racing-build-2016.506651/

Thanks, good to know. There's definitely play in the pedal before the rod moves. I did a rough measurement today and there's around 10mm of initial play from its uppermost position (which I really have to pull on the pedal to reach and probably isn't as high during regular use), till it meets resistance from the spring, then another 3-5mm of play before the rod starts to move.

The pedal does almost touch the floor when I really press on it. Is that bad and should I adjust something to fix that? The FSM says at least 55mm to the floor when fully pushed in, and I think it's more like 10-20mm, rough estimate. And max height's around 150mm tops, and the FSM says it should be around 180mm. Do I have some work to do there?

 

[We're on Boost]

The pedal does almost touch the floor when I really press on it. Is that bad and should I adjust something to fix that? The FSM says at least 55mm to the floor when fully pushed in, and I think it's more like 10-20mm, rough estimate.

Well that 55mm to the floor is not with the pedal pushed all the way in.
It is supposed to be the point at which the clutch is at the very edge of being completely disengaged.
It's like this: With the engine running and you have it in gear with the clutch all the way pushed in, and you start to let the clutch pedal out slowly until you just start to feel or hear the engine revs being pulled down a little because the clutch is starting to engage - that is where "D" is. Kind of hard to get an actual measurement of that , car running and all. But that is the idea.
This is measurement "D" on page 6-5 of the FSM:

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its uppermost position (which I really have to pull on the pedal to reach and probably isn't as high during regular use),

This part I'm not sure about, whether you should be able to pull the pedal up at all from its resting point.
If your car had cruise control, then maybe it is compressing the clutch switch when you pull the pedal up.
But I don't think you should include that pull-up distance in your measurement.
I'm not a good one on this because, yeah my car was cruise control, but that clutch switch was taken out of my car way back in 2004 when I first had an ACT 2600 clutch put in the car. We needed the extra clutch pedal travel to get enough throw on the clutch, so that switch came out. That let the clutch pedal come out (or up) farther. I never measured how high the pedal was before we did that.

So here's something a little weird. On my car even with that switch out, I now get almost exactly 180mm on that measurement you are talking about where the FSM says it should be 180mm! What would it have been when the switch was still in there?
I have no idea, but it must have been less. So maybe your 150mm is not that unusual, but it sounds pretty slim to me. Maybe you should try turning the clutch switch to adjust it for more pedal height, per item #2 on page 6-5 of the FSM.

The most important thing though is that you have enough travel in the pedal to get full disengage and then some. If your "D" point is at a point where you still have about 1" more pedal travel before the pedal arm goes into the carpet, that I think is good, and that comes out to about the 55mm that they show for "D" in the FSM. If your "D" doesn't come out big enough, I suppose you would need to adjust the clutch switch a ways, then readjust the master rod.

I'll throw in a pic of mine where you can see that my clutch switch is removed, and the pedal is full up, or out, so the pedal stopper parts are touching. You see empty threads in the bracket where the switch was.
Down in the picture is forward in the car. Camera is looking up.

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It might be that your new clutch needs more throw at the TOB than a stock clutch.
Just reading the SBC Stage 2 DD description, it says "increased clamp load with little or no increase in pedal pressure".
The only way I know of doing that is by moving the fulcrum closer to the load. Like in a lever system.
When you do that, you have to move the TOB farther to get the same amount of movement of the load, with the upside that you don't have to push any harder on the TOB. You just have to push it farther.

 

[XC92]

My car came with cruise control and the switch is still installed in front of the clutch pedal. I'm going to raise the front end today to do an oil change and swap out the stock struts, so I'll also check rod and fork movement and resting/fully pushed out positions and see if they look good in addition to measuring all the pedal-related distances.

IIRC when the clutch is engaged (i.e. the pedal isn't pressed in) the fork end is slightly to the right of the center of the fork opening in the trans (meaning towards the driver's side), and I believe that's where you want it to be so there's no preload and the pressure plate spring is fully pressing against the clutch disc, which is fully engaged. Right?

If so, then given my rough pedal distance measurements and what everyone's told me here, it looks like everything's the way it should be and no adjustments are necessary, so all I need to do now is take more accurate measurements to confirm this, i.e. pedal free play (when I don't pull on it further back in its resting position against the cruise control switch), height when clutch is fully engaged and disengaged, distance to floor when fully disengaged, etc. Right?

If so, then all I really need to do now is resurface the old stock OEM flywheel, or replace it. But I won't be able to get to that until I'm ready to fix a trans issue where it often pops out of 1st gear when under load. Interestingly, with the new clutch, fluid and slave and everything bled, it doesn't pop out as often as it used to, whereas it ALWAYS popped out with the old clutch (which was almost completely worn down when the popping out issue first started). So it's true that bad clutches are a major reason for trans issues?

 

[We're on Boost]

IIRC when the clutch is engaged (i.e. the pedal isn't pressed in) the fork end is slightly to the right of the center of the fork opening in the trans (meaning towards the driver's side), and I believe that's where you want it to be so there's no preload and the pressure plate spring is fully pressing against the clutch disc, which is fully engaged. Right?

Yes, with pedal out, there is no hydraulic pressure in the system, because the port to the master cyl reservoir is open. So no preload on the clutch fingers, except for the small preload you get from that little spring in the slave cylinder:

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As for the fork being slightly toward the driver's side from center, this should be fine if it is only a little. It might even be optimum. You'll see a lot of posts in here where people are shimming the pivot ball to get the fork positioned like that, and usually they will say that it solves or helps their problem of insufficient release.

It's a peeve of mine that the FSM doesn't say where the fork should be. Centered, left, or right.

The FSM shows like a cross section assembly drawing on page 6-18 of the fork, slave, and pivot ball, where the fork is actually slightly left of center. This bugs me a little because all the years that I worked as a mechanical engineer at Boeing and a couple other places, when we made assembly drawings, they weren't cartoons. They meant something, and they would almost always show the parts in their nominal position. I look at this drawing and I don't know if it is supposed to be just a cartoon or what.

Yes I think if you confirm those measurements in your 3rd paragraph, that should do it.

As for the trans popping out of 1st being related to a worn out clutch, I don't know. I've had worn out clutches before and it didn't make the trans pop out of gear, and it's not obvious to me that it should be happening that way.

 

[XC92]

So, if I'm understanding correctly, this is a breakdown of the 5 stages of pedal movement:

1. Pre-free play, if you pulled the pedal back against the cruise control switch
2. Free play, where the MC rod doesn't yet move
3. MC rod moves, but reservoir port still open, so no fluid pressure to SC
4. MC rod moves, reservoir port shut off, pressure to SC, clutch disengaging
   
5. Clutch fully disengaged, but pedal can still be pushed towards floor, to no effect

If so, I have to verify that the max and min pedal heights, and movement, are within FSM spec, and make adjustments accordingly if called for, otherwise I'm good to go, right?

 

[We're on Boost]

Those 5 points look correct to me.
As for the measurements A, B, C, D on FSM page 6-5:
"D" is very important. Note that they give it as a minimum. 2.2" or more.

"B" I kind of lump into "C". In other words, B is a part of C, or C includes B.
Anyway I don't bother trying to determine B. I let C be the whole determiner of that part of it. This is assuming that you define "C" as the point where the MC rod starts to move.
Right now my "C" is only 1/8" and that seems to be fine. It stays consistent and works and I need the little extra throw it gets me, vs having a larger number there. But staying within the range they give in the FSM is probably the best if you aren't fighting lack of throw.

"A" we've talked about and I'm not sure what you are going to wind up with there. If you can get D and C to come out right, then I think you are good even if A seems a little short. Measuring A can be a little vague. Measure down from the inboard side of the pedal, because on the outboard side the floor is starting to come up already, resulting in a shorter measurement. Also be sure to measure perpendicular to the floor like they show in the diagram for measurement A in the FSM.

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[XC92]

I just wanted to be thorough, realizing that some of these aren't that important (so long as they're not TOO out of whack). And while 4 (D) is very important, I think that so are 2/3 & 5. 2/3 because you need some "slack" before disengagement begins or else even a light tap could lead to slipping and weak, and 5 because you don't want full disengagement when the pedal hits the floor. These probably become even more important as the clutch disc wears and clutch fluid breaks down, as these are going to cut into either "free play".

I'm still not quite sure why you ever have to adjust any of this when replacing a clutch disc, since the whole mechanism is supposed to self-correct and allow for wear.

 

[We're on Boost]

Well 2/3 are important because you want to be sure that the port to the reservoir is always open when your foot is off the pedal.

Yeah I agree that if you are just changing a disc, you shouldn't need to adjust anything. The fork position and therefore the position of the slave rod will change a little but so what. That just changes the total volume of the fluid that is in the system, which is ok. You don't change the MC rod adjustment for that. The master piston is always supposed to be hard against the aft end of the master cylinder when your foot is off the pedal. Once you have that right, it shouldn't change just because of disc wear, or putting a new disc in.

 

[XC92]

Then when would it ever be necessary to adjust all this, if your fork, fulcrum, throwout, slave, lines, fluid, master, etc., are all in good shape w/o excessive wear? Is it for when you get some monster clutch or a dual plate clutch or unusual flywheel? There just seem to be so many people saying "You MUST adjust your clutch pedal, rod and jam nut whenever you get a new clutch or TERRIBLE things will happen!" (slightly exaggerated by me for effect).

 

[We're on Boost]

I would say you should check the measurements when you get a new clutch. But I wouldn't be surprised if the measurements were all still good.
Wear of the parts in the pedal assembly would gradually increase the pedal free play C. Then you are going to lose some of your D. So that's pretty important to know about.

For example, on my car the "D" is barely adequate if it even is. It's been like that ever since I started using ACT 2600 (now 2700) clutches. So trying to get as much D as possible, I've reduced C to 1/8" and took out the clutch switch to maximize A. Then due to probably wear in the clutch pedal assembly, and flex in those parts, there is some lost motion in the mechanical stuff under the dash board. Which of course makes the problem worse. So English Racing welded that nut onto the master clevis, which has the effect of making the master rod about 4 turns longer, to allow for more adjustment. Thread pitch is 1
1.25mm on that rod, so I'm saying like about 4mm or 0.160" longer. So I can pretty much adjust the slop out of it, but I've still got the flex.
All because of the clutch that needs longer throw, and is much stiffer sprung so it pushes back harder causing more flex in the mechanical parts which are not perfectly rigid, and actual wear (slop) in some of those parts due to lots of use (age).

Your car is a lot lower mileage than mine (mine is 143,000 miles now) and yours has always had a stock clutch in it, so I hope that you are in better shape than most of us on the mechanical wear of those parts under the dash.

 

[XC92]

So I got down there again today and measured things as best I could. First, I'm confused about what the FSM says. It says the clevis pin play should be 1-3mm and the pedal play 6-13mm. I don't understand which is which.

The "play" that comes from pulling on the pedal from its normal resting position to as far as it can be pulled, what I referred to above as #1, is 11mm. Is that pedal play?

I can then move the pedal down around 5-6mm before the MC rod moves. Is that clevis play?

While it's impossible to know for sure with the engine off and can not moving (and obviously unsafe to try unless the car is fully raised), I think that the clutch is fully disengaged when the pedal is around 50-60mm from the floor, which is per the FSM spec.

Finally, the height of the pedal at rest is around 142mm, and 153mm is when it's pulled back as far as it'll go. These are well below the 176-181mm FSM spec. Not sure what's going on there and if I measured properly. There is a pretty thick carpet there (stock), but I doubt it accounts for the missing 25-25mm. However, the FSM also says that the full pedal stroke is 151mm, which is in line with my measurements. It's so confusing! Videos I've seen haven't helped, making it seem like you're an idiot if you don't immediate understand what's going on.

To go with my pedal movement breakdown above:

1: 11mm
2: 5-6mm
3/4: 94mm (combined because I can't tell when the port hole is blocked)
5: 55mm

Look, the clutch engages and disengages properly and doesn't slip, as far as I can tell. There's some pedal movement before it begins to disengage, and some more movement after it disengages, and when I released the pedal, it engages again. If it slipped then I'd feel some shuddering or hesitation, and smell the organic friction surface burning (a smell I'm familiar with from back when I first started driving the Talon and got used to the clutch). I'm not smelling it.

So most likely I'm ok. I just wish the FSM agreed. And you're probably right. Between fewer miles than most on a DSM this old, stock clutches, PPs & flywheel, no power mods, no launching or racing, or overly aggressive driving or heel and toe, it's probably too soon for this sort of wear and tear to manifest itself in the pedal-rod assembly.

 

[We're on Boost]

I agree that the way the FSM lays this stuff out, it does not define the terminology. It's pretty bad.

The "play" that comes from pulling on the pedal from its normal resting position to as far as it can be pulled, what I referred to above as #1, is 11mm. Is that pedal play?
No. The clue for me is, look at the drawing for "C". They show the pedal in the upper position in solid lines, and in the slightly lower position in dashed lines. The solid lines would be the initial position. From there, you push the pedal down (to the dashed position) and that is the "pedal free play". They are not talking about pulling the pedal up.
Down is the same direction you go to measure "B" which is the clevis pin play, and which they give as a smaller number. This is why I say that B is a subset of C. As far as I'm concerned you can just forget about B. Take care of both B and C by just measuring C.
The pull-up measurement is something they don't even talk about and is irrelevant anyway because it is something you don't use while operating the car.

I can then move the pedal down around 5-6mm before the MC rod moves. Is that clevis play?
No. From where the pedal is at rest, to where the MC rod starts to move, is what I call pedal free play. It is the amount you can move the pedal that doesn't actually do anything (except it takes up slop). If you define it this way you are safe, because this way you know for sure that the master piston is fully retracted (all the way aft) when your foot is off the pedal.

Now if you are curious about how much wear there is on your clevis pin (#13), and the hole in the clevis and the hole in the master lever (#17) that the clevis pin goes into, you would be down there wiggling the pedal back and forth while trying to watch that clevis area. And you could after watching that stuff for a while come up with your own method of measuring "clevis pin play" in terms of pedal movement. And if it was gross you might decide to try to get new parts to replace them.
If you aren't having trouble getting enough throw on your clutch, you probably won't need to replace those parts.


If your C and D measurements come out ok, then you should be getting enough throw on your clutch. That's why I say that C and D are really the important ones. Then of course it has to act ok while you are driving. When you are going into a gear, you don't want any feeling that there isn't enough disengagement. That could cause some grinding.

That 151mm, hmm, pedal stroke is different from how they show "A". Because for A, they are measuring from the top face of the pedal to the floor. You can't actually move the pedal that far. I've always figured that my full pedal stroke is about 6 inches. That's darn close to 151mm.
Anyway what's going on here is that when you have the "pedal all the way to the floor", it is actually the pedal arm about half-way up the arm that is running into the carpet. The top face of the pedal is still an inch or so above the floor. So like on my car, I measure A as 7 inches, but the actual pedal travel is only about 6 inches.

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[XC92]

So if my pedal's play is around 11mm, that's within spec, and forget about the clevis play. But is a total pedal throw that includes play of 94mm, or one that doesn't count play, from where the rod begins to move to where the pedal hits the floor, of 83mm, ok? Or is something off, given that the max pedal height even after I pull on it is 153mm? Something's not right here and I suspect that the FSM is at least partly to blame. If the pedal height was actually 180mm, it would be too high for many drivers' comfort, especially tall ones.

 

[We're on Boost]

The pedal throw of 6" and measurement A of 7", both of those include the pedal free play.
In post #39 where you said your 3/4 was 94mm, I wasn't sure what you meant, but I thought maybe it was pedal stroke from the pedal at rest, down to where the clutch is disengaged. I'm still not sure what the 94mm is though.

 

[XC92]

Yeah now I'm confused about the 94mm. I think I meant that the pedal throw from its normal resting position (without my having pulled on it) to the floor (i.e. beyond clutch disengagement, to where it can't be pushed anymore), but by my measurements that's actually around 120mm, or 142mm minus whatever the thickness of the pedal is.

Does that sound ok? But with my setup, there's no way my setup's going to be anywhere near the numbers the FSM gives for height or throw.

 

[We're on Boost]

By the way I was just out looking at it on my car, and I messed up when I said the pedal hits the floor some ways up the arm. Actually it hits the floor right smack underneath the pedal. So your pedal stroke, the way they measure it in the FSM, would be like you said just now, 142mm minus the "pedal thickness". The stock pedal thickness I can't really measure because I have aftermarket pedal covers on there. But it looks to me like the pedal thickness of the stock pedals would be about 1". I think 1 inch is what they are figuring for it in the FSM. Because they say "full stroke" is 6.0 inches. Their A is 7 inches. So their "full stroke" must be 7" - 1" = 6".
Yeah 142mm seems short for A. On my car, where I do have A=7 inches, my clutch pedal is a little over an inch higher than the brake pedal. I think I measured 1.25" higher, but I didn't write it down. It works out ok for me, has never bothered me.

But for the really important thing which is does your clutch get enough throw for healthy disengage, I guess you should just try it out.
So, if you are starting the car with the clutch pedal in anyway, put the car in gear before you start it. Then, clutch pedal is on the floor, it's in gear, start engine, and slowly let the clutch out just a little bit until it bites a little bit. Push it back in and let it out to first bite again. Just do that a few times and get a feel for how far you think you are moving the pedal from the floor to that first little bite point. That should be a little over 1 inch.

If you've done this test and it seems ok but you want to get more like an actual measurement of it, I suppose you could put a small block of wood of known thickness on the floor under where the pedal hits, and try the engine start test again. The block would have to be about 1" thick, maybe 3/4" to start with. And you'd need some room around the car in case it wants to go. Well you would need some room anyway, even without a block under there.

If you try to figure out what that distance should be from D (which is supposed to be about 2.2") it should be 2.2 minus the "pedal thickness" of 1 inch. So a throw of about 1.2" is probably what they would say in the FSM, if they were giving it in terms of throw. For a minimum.

If you just aren't getting enough there for a good D, you'd have to mess with the clutch switch adjustment, bringing the whole pedal range up farther from the floor.

 

[XC92]

If my A is short, then the FSM says I need to disconnect the cruise control switch and turn the connector enough so the pedal moves up to where it should be. But that only makes sense if I pull the pedal up, because the clutch pedal assembly spring doesn't push it there by itself, as we discussed above. To get the FSM A value of 176-181mm, I'd have to do both.

Plus, I'm not even sure there's room to move the cruise switch up enough to get to even 176mm. Something's not quite right. Either I'm not understanding or measuring things properly, the FSM is wrong, or there's something wrong with my clutch pedal assembly, either due to wear and tear or mods some mechanic did years ago without telling me (or maybe they did and I forgot).

But, as you say, if I'm able to fully disengage the clutch before the pedal hits the floor, and the clutch fully engages before the pedal returns to its resting position, i.e. there's "play" beyond both full disengagement and full engagement, then I should be ok even if the numbers aren't quite right. Only way to tell for sure is to drive it, ideally in an empty parking lot where I can safely test this all out and confirm that all is well.

I think to test full disengagement I can push the pedal to the floor, put the car in 1st, then rev the engine. If the car doesn't move, it's fully disengaging. While continuing to rev the engine, I can then slowly release the clutch pedal until the car starts to move, sensing how much I released it to see where engagement begins, at which point I disengage again.

What I'm not so sure about is how to test upper free play, to make sure the clutch is fully engaged when the pedal is at rest and there's zero slipping. But I suppose that this can be done with the engine off, by noting the position of the fork when the pedal is at rest. I've already done this and it's a bit to the right of center, towards the driver's side, which is as it should be.

 

[We're on Boost]

"the clutch pedal assembly spring doesn't push it there by itself"
It should. That spring is part #9 in the diagram up in post #40.
It's called the "Turn Over Spring" for a good reason. Now here I'm going on memory from when I had my master cylinder out, so I could get something messed up. But when my master cylinder was out, I did a lot of playing around with the pedal which was all still installed in the car, I didn't take out any of the pedal assembly, not even the clevis. The clevis and parts 17 and 9 were still all assembled in there, so the spring was still attached to the whole pedal assembly.
Anyway, with no master cylinder attached, what I found was that if I pushed the pedal down (from the full up position) I would be getting resistance for the first couple inches from that spring. Then about half way down to the floor all of a sudden whoops, pedal zaps to the floor all by itself.
What was happening is that spring goes "over center" and then it pulls the pedal down instead of pushing it up.
It's an over-center mechanism, like you have in a light switch or most any toggle switch.
Somebody please correct me if this is wrong. This is just my memory of it.

The turbo cars don't have the spring shown as part #1. They have the spring part #9 only.

Your pedal not coming up all the way, I took that to be that probably it comes up to the switch, then it is pushing against the switch, and maybe it doesn't push the switch all the way in. I just figured there was some travel left in the switch and that's why you could pull the pedal up farther. But that's just a guess.

I think if you didn't have such miserable conditions to work in (outside, winter, etc) and if you had a mechanic mirror on a stalk and some portable light, you might be able to figure out how that switch is acting mechanically just by watching it without even taking anything apart. You might even be able to take some video of it, holding your phone up there. Sometimes that's a good way to see something.
Hopefully your spring is working correctly. That area in my car is not very affected by rust or any type of corrosion. Hopefully yours is similar.

If you want to test it the way you described in post #45, that's ok, but test it the other way first (the way I described in post #44).

"What I'm not so sure about is how to test upper free play, to make sure the clutch is fully engaged when the pedal is at rest and there's zero slipping."
Well you've already measured pedal free play and we have pedal free play defined as pedal travel before the master rod starts to move. So you should be ok on that.

 

[XC92]

I wonder if the switch that the pedal hits on its way back up is too far down and needs to be adjusted back up per the FSM? I don't know if it's related, but I do recall that back when the car was working, the cruise control stopped worked during the last few years. Since I didn't use it that often I didn't try to fix it, and figured it was either loose or faulty wiring or a bad contact somewhere. But maybe that switch isn't being pressed in fully by the pedal and spring, which tells the ECU that the clutch is disengaged, which turns off the cruise control. That's what that switch is for, right? If so, I wonder why it's not being pressed in, because the spring is worn out, there's something resisting it like a worn bushing or obstruction, or the switch is too far down.

Btw what's the other switch on the pedal for, on the other side of he pedal arm? Does it tell the ECU that the clutch is disengaged, and the other switch tells it that it's engaged, sort of a fail safe system that doesn't rely entirely on one switch being on or off since switches break but rarely at the same time? I.e. if the upper switch is unpressed and/or the lower switch is pressed, the cruise is turned off, and is only turned back on if the lower switch is unpressed and the upper switch is pressed, to prevent the cruise from coming on and surging the throttle and thus engine when you're trying to change gears, which is bad for the engine if done repeatedly and can launch the car when you don't expect it?

This is what I mean:

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The clutch pedal lever is on the left, the upper switch is above it and black and the lower switch is below it and grey/white and partly obscured by the pedal lever.

 

[We're on Boost]

That's a good picture!
Yes if there is something wrong with that upper switch, it could be why your cruise control quit working.
So in the picture, I see the switch plunger sticking out a ways and I don't know if that is normal when the pedal is up.
I marked up that distance with red dimension lines and posted it.
I'm suspecting it's not normal, because in the FSM on page 6-5 you can't even see the plunger - it's pressed all the way in. Posted a shot of that too with it turned upside down so it looks more like the photo.
In the FSM drawing, the rubber bumper that moves with the clutch pedal arm is right up against the threaded body of the switch.

So kinda looks like there is something going on there but I don't know what.
It would be interesting to take that switch out and see what the pedal does then.
I think you said before that when you pull the pedal up that last little bit, you have to pull pretty hard, right? Maybe that switch is jammed up inside.

The other switch, the one you hit when the pedal is to the floor, that one just enables the starter. You know, have to push the clutch in for the starter to work. Actually it enables the starter relay, which enables the starter circuit.

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[XC92]

Actually, I'm referring to a third switch, which you can partly see below and to the left of the pedal arm in the photo above. IIRC the pedal presses on it when the pedal is pressed. Or maybe it's unrelated to the pedal and just happens to be near it. It's the one that's fully visible in the photo you posted above in comment #30, just below and to the left of center, left of the clutch pedal. It's grey and white. What's that switch for and what presses on it?

As for the cruise control switch not being fully pressed in when the pedal is at rest, something is clearly preventing the spring from pushing the pedal arm fully onto it. It could be a worn spring, dried up lubrication, worn pedal arm bushing, alignment issues, something in the way or rubbing against a sliding part, etc.--or it could be that the switch is too far up to allow the spring to push the pedal fully onto it, as per the FSM. While I don't have to pull hard on the pedal to get it to fully press the switch in, I do have to pull on it, so there is "play" there.

Perhaps the solution is to temporarily remove the switch connector, loosen the switch jam nut, thread the switch closer to the pedal arm, tighten the jam nut and reconnect the switch, which is what the FSM recommends. I'm just wondering what could have caused this to happen. Could it be a bad MC that's preventing the rod from coming out all the way? Bent pedal arm or other part of the assembly? Maybe some mechanic did this years ago and I never noticed? Does the switch look like it's too far up? I can't compare it to yours because you clearly removed it.

I'll try to press on the switch plunger while pushing the pedal down to see how much resistance it gives and if it feels excessive. Maybe it's just a bad switch. I can live without cruise control for now, as most of my driving is on streets, but it is something I'd like to fix at some point in anticipation of highway road trips. I'll also have a look-see to see if anything else might be keeping the pedal from fully depressing the switch plunger.

 

[We're on Boost]

The gray and white switch with the white plunger that's fully visible in post #30, that is the switch that enables the starter relay. The FSM page 6-5 calls it the "Interlock" switch. The thing that presses on it is another rubber or plastic bumper that in my car has turned sort of an orange color. When my pedal is to the floor, the white plunger is sticking out by about the amount they say in the FSM. In the pic below I have a red arrow at the orange thing, and you can see the white plunger. Clutch pedal is all the way up.

There are only 2 switches on the clutch pedal, so any 3rd switch in the area must be something else, maybe the one on the brake.

Yeah I really don't know what is keeping your clutch pedal from coming up farther. I think most likely it's a jammed up cruise control switch. But if it isn't that, then the other possibilities get a little uglier probably for the fixing of them.
When I had my master cylinder out, I probably should have taken more time to figure out that spring #9 a little better. It seemed to be working ok so I just didn't think about it that much.

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