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Discussion Starter #1
Hey guys.
Last night was driving the V with no issues. Wife wanted to run into hobby lobby for a quick minute. I've been married long enough to know nothing takes a quick minute at hobby lobby and her. So I sat in the parking lot idling in the car for the expected 30-40 minutes. When she finally came out I went to leave and the clutch pedal is now much lower and is releasing/engaging right near the floor. It has been level with the brake pedal , now it's much lower....any ideas what's up? It's still in the same low position this morning after sitting overnight.


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Check your fluid level in the master cylinder (inside the engine bay next to the brake cylinder). Are you leaking fluid under the car?
 

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Ugh. Dropped pedal is definitely a hydraulic issue whether it is just old and needs bled versus a real leak remains to be seen.

Fill it up, bleed for air and check for leaks. Without knowing mileage or specifics, my first thought would be either bad master cylinder or slave (if no fluid is seen, I'd suspect internal leak in the Master).

So check the transmission bell housing for fluid, follow the hydraulic cable up to the master next to the brake booster and then check the reservoir- does the fluid look black?

Fill the reservoir, pump the pedal by hand a dozen times, suck out the fluid with a syringe and repeat a few times to see if the pedal comes back.

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Check your fluid level in the master cylinder (inside the engine bay next to the brake cylinder). Are you leaking fluid under the car?
Nope, no sign of fluid leaving. Will look at fluid level when I get back around the car.

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Ugh. Dropped pedal is definitely a hydraulic issue whether it is just old and needs bled versus a real leak remains to be seen.

Fill it up, bleed for air and check for leaks. Without knowing mileage or specifics, my first thought would be either bad master cylinder or slave (if no fluid is seen, I'd suspect internal leak in the Master).

So check the transmission bell housing for fluid, follow the hydraulic cable up to the master next to the brake booster and then check the reservoir- does the fluid look black?

Fill the reservoir, pump the pedal by hand a dozen times, suck out the fluid with a syringe and repeat a few times to see if the pedal comes back.

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Cars only got 37k on it

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If the clutch reservoir is still full - you're probably in good shape and just need to "flush" the system - which is what I described briefly above:

You suck out the old dirty clutch fluid with a large automotive syringe, replace with clean fluid. Then manipulate the clutch pedal a few dozen times to mix the new fluid into the system - repeat the removal / replacement / clutch pumping procedure until you get mostly clean fluid after pumping the clutch multiple times. It could take quite some time and a dozen cycles or more to get the fluid mostly clean, and is a byproduct of the "self-bleeding" design and the exposed slave cylinder that blesses you with a contaminated hydraulic system that is not easily bled. Doing this should give you a firm pedal and no further issues. if it doesn't, then an internal leak (failed) master cylinder becomes much more likely.

If the clutch reservoir is empty or very low, then you have a leak and will need to find it. A leak strongly suggests a failed hydraulic hose connector or the slave cylinder. If you're really lucky, it's the slave - which means pulling the transmission and finding a $250 replacement slave cylinder that's probably on backorder after the UAW GM strike! lol.
 

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Discussion Starter #7
If the clutch reservoir is still full - you're probably in good shape and just need to "flush" the system - which is what I described briefly above:

You suck out the old dirty clutch fluid with a large automotive syringe, replace with clean fluid. Then manipulate the clutch pedal a few dozen times to mix the new fluid into the system - repeat the removal / replacement / clutch pumping procedure until you get mostly clean fluid after pumping the clutch multiple times. It could take quite some time and a dozen cycles or more to get the fluid mostly clean, and is a byproduct of the "self-bleeding" design and the exposed slave cylinder that blesses you with a contaminated hydraulic system that is not easily bled. Doing this should give you a firm pedal and no further issues. if it doesn't, then an internal leak (failed) master cylinder becomes much more likely.

If the clutch reservoir is empty or very low, then you have a leak and will need to find it. A leak strongly suggests a failed hydraulic hose connector or the slave cylinder. If you're really lucky, it's the slave - which means pulling the transmission and finding a $250 replacement slave cylinder that's probably on backorder after the UAW GM strike! lol.
Fluid looks clean and it's up to the full line

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Does the clutch work properly now?

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Does the clutch work properly now?

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Other than pedal location and the engagement/ release happening right off the floor ,yep its working great.

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Other than pedal location and the engagement/ release happening right off the floor ,yep its working great.

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My money is on the slave failing internally...
 

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My money is on the slave failing internally...
You mean the master?

I'd expect the slave to leak heavily if it fails.

It's worth doing the ranger method to replace the fluid and see if that brings the pedal back. It would be really uncommon for either slave or master to fail out of the blue. I'm wondering if he just has contaminated fluid?

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There is not a logical explanation that explains the change in pedal with no fluid lost and both hydraulic mechs acting as they should...not to me at least

I dont know the internals of the master nor slave, but you have pressure being applied and then released...if that relationship in pressure app and release changes, so does engagement point and the pedal returning. Sounds to me like an internal seal failing that is changing pressure application to be delayed relative to pedal ROM.

Just my thoughts.

Im talking internal system leak. Any external system leak would piss fluid and lose function eventually.

OP, you dont hold the clutch in at every stop do you? Rode with a coworker the other week in an M car and thats all he did...wtf dude.. throwout bearing no likey that.
 

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I don't disagree with you Bro! But the entire presentation is atypical.

Changing the Master is a bitch, the slave even worse - it's much easier to go for the low-hanging fruit here: flush the clutch fluid and see what happens.

If the clutch fluid is contaminated with moisture, the extended heat from idling whatever might have caused air bubbles, accounting for the dropped pedal - much like old brake fluid.

Easy enough to try before replacing parts.

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Yea I was just placing my bet, not telling OP steps to take Bro :)

swap fluid (is a bitch in of itself) and then proceed, definitely wise approach.
 

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Discussion Starter #15
Update on pedal. Drove it 30 miles in a good bit of traffic to take it to the dealer this morning. No change in pedal height at all. When I got there the tech reached in and pulled it up and it's been normal since. Fluid is clear and clean. Cylinder is full , springs in place, Everything's working as it should. I had previously put the tip of my shoe under it and tried to pull it up and it wouldn't budge.....go figure. Everyone there was like wtf happened, never seen it before. Just sitting and idling and pedal lost half it's travel without ever touching it????? If weird one off shits gonna happen it's going to be to my car.

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Fluid dude. You probably have contaminated (with moisture) fluid.
 

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Didja figure this out?

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