Clutch pedal stuck @ floor and now mushy... hydraulics or PP?
12-04-2006, 01:13 AM
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Clutch pedal stuck @ floor and now mushy... hydraulics or PP? A little background info:
I've got an '05 Cadillac CTS-V with the TPIS slave cylinder spacer, stock iron C5 Z06 flywheel, clutch and pressure plate (takeout from a low-mile '04 Z06). Eliminating the factory dual-mass setup has been mostly beneficial, despite using the less-grippy and weaker Z06 OEM clutch.
I do enjoy driving hard every once in a while, but I generally keep it easy on the streets. I've had this clutch in my car since May with no problems. Yesterday I had a little run with a 350Z; after running it hard in second and third, my clutch pedal sunk to the floor when I came to a stop. I actually had to pick it back up with my toe and then carefully drive it home.
Today I tested the clutch and noticed a weakened feel in pedal pressure. The clutch master cylinder was also nearly bone dry, which seems a little weird, but I know it's happened to other CTS-V owners. I topped it off with fluid and then drove it around the block a few times, banging upshifts to test the pressure plate. It held and engagement felt normal, but the clutch pedal still feels soft.
Now I'm thinking I might have a small pocket of air in the clutch hydraulics, which is the cause for the weak pedal. I figured the pressure plate can't weaken so dramatically, and if it had, it wouldn't be able to hold the 3800# car on a firm upshift. The clutch pedal seems to depress without as much resistance and is a bit slower to return than normal.
Are my assumptions true, and will it bleed itself after a couple days of driving, or will I need to pull the slave and bleed it manually? Is there a chance the pressure plate has weakened, and what's the expected life of the factory Z06 clutch disk and pressure plate on a mild daily-driver?
I've got an '05 Cadillac CTS-V with the TPIS slave cylinder spacer, stock iron C5 Z06 flywheel, clutch and pressure plate (takeout from a low-mile '04 Z06). Eliminating the factory dual-mass setup has been mostly beneficial, despite using the less-grippy and weaker Z06 OEM clutch.
I do enjoy driving hard every once in a while, but I generally keep it easy on the streets. I've had this clutch in my car since May with no problems. Yesterday I had a little run with a 350Z; after running it hard in second and third, my clutch pedal sunk to the floor when I came to a stop. I actually had to pick it back up with my toe and then carefully drive it home.
Today I tested the clutch and noticed a weakened feel in pedal pressure. The clutch master cylinder was also nearly bone dry, which seems a little weird, but I know it's happened to other CTS-V owners. I topped it off with fluid and then drove it around the block a few times, banging upshifts to test the pressure plate. It held and engagement felt normal, but the clutch pedal still feels soft.
Now I'm thinking I might have a small pocket of air in the clutch hydraulics, which is the cause for the weak pedal. I figured the pressure plate can't weaken so dramatically, and if it had, it wouldn't be able to hold the 3800# car on a firm upshift. The clutch pedal seems to depress without as much resistance and is a bit slower to return than normal.
Are my assumptions true, and will it bleed itself after a couple days of driving, or will I need to pull the slave and bleed it manually? Is there a chance the pressure plate has weakened, and what's the expected life of the factory Z06 clutch disk and pressure plate on a mild daily-driver?
12-04-2006, 11:53 AM
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+1 on the bleeding. When I did the clutch in my Z28, I buttoned everything back up ASSuming the Slave was pre-bled, it sunk like a rock when I stepped on it.
Might have blown out the slave. But cheap and easy first, start w/ the bleeding.
Might have blown out the slave. But cheap and easy first, start w/ the bleeding.
12-05-2006, 06:29 PM
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I have one that did the same thing. At first it was fine then all of a sudden it went to the floor and I had to pull it back up with my hand. It worked fine for a little while afterwards, but then it did the same thing. It feels like it needs bleeding but i tried to mityvac it and got no bubbles from it. Is the slave just gone bad or what? I hate to pull a transmission if I don't have to.
