What is actually going on with sticky pedals?
09-01-2008, 07:23 PM
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What is actually going on with sticky pedals? Like so many, I suffer from the dreaded stick pedal in my swap car. I have tried bleeding and bleeding some more, to what seems like no avail. I also discount the circulation theory on changing fluid in the reservoir, mine can be clean up there and filthy coming out when bled.
So, what exactly is going on here? I've noticed I can drive my car fairly hard and shift at 5K and while the pedal falls a little, I can keep on shifting. Up that to 6K, and forget it, 1-3 and its on the floor. Pump it once or twice a few second after the fact, and I'm good to go again. Where is the fluid going? I don't seem to be losing any at all in the system, and a bad master doesn't seem to make sense. If it was bleeding past the seals in the master, wouldn't I be losing fluid? Wouldn't sitting with the clutch depressed for long periods of time eventually allow the clutch to engage as pressure is released? Why would that happen only in the 1/2 second required for a WOT shift? I'm not sure I buy the heat argument either. I can sit in traffic all day long, slipping the clutch as I have 3.08's, with high coolant temps, and not get the pedal syndrome.
I guess I'm looking for a better idea of what is actually going on here instead of just throwing money at parts I don't have reason to believe are bad? I'm also curious how many of us have this problem a it relates to the return spring. I'm not running one. Does anyone with a good functioning spring have this issue?
So, what exactly is going on here? I've noticed I can drive my car fairly hard and shift at 5K and while the pedal falls a little, I can keep on shifting. Up that to 6K, and forget it, 1-3 and its on the floor. Pump it once or twice a few second after the fact, and I'm good to go again. Where is the fluid going? I don't seem to be losing any at all in the system, and a bad master doesn't seem to make sense. If it was bleeding past the seals in the master, wouldn't I be losing fluid? Wouldn't sitting with the clutch depressed for long periods of time eventually allow the clutch to engage as pressure is released? Why would that happen only in the 1/2 second required for a WOT shift? I'm not sure I buy the heat argument either. I can sit in traffic all day long, slipping the clutch as I have 3.08's, with high coolant temps, and not get the pedal syndrome.
I guess I'm looking for a better idea of what is actually going on here instead of just throwing money at parts I don't have reason to believe are bad? I'm also curious how many of us have this problem a it relates to the return spring. I'm not running one. Does anyone with a good functioning spring have this issue?
09-02-2008, 07:42 AM
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same issues here. i think a better diagnosis instead of replace this and that. i am going to try and bleed my crap today and see if that helps. there is a service bull at gm but for mostly vette owners. should work for f-bodies though. centrifugal force has something to do with it i think. i know a trans guy who swears its a problem with ls series clutch plates.