I'll start by saying I have been looking for a thread to help me with this problem but none have all these symptoms...

I have a freshly built (1200 miles in last 3 weeks) LS vtech turbo del sol 93' with brand new stage 4 hydraulic clutch with lightweight fly wheel. The clutch has maybe 2000 miles on it.

Problem when engine cold: after car is started the RPMs drop when clutch pedal is pushed in and slight pulsing in pedal.

Problem when engine is warm: RPMs still drop when clutch pedal is pushed in. Pulsing gets worse and sounds almost like a knocking noise when pushed in. When pushed in and engine us reved, makes louder knocking, more rapid pulse of pedal. When my foot is resting on the pedal pulsing is still felt all the way thru pushing to the floor. When driving there are times when I push the clutch in and the pedal does not come up, I need to put my foot under it to get it to come back up. Also when driving the clutch fluctuates in engagement when clutch is released. The clutch is not nearly as hard to push as it was 3 weeks ago when I got the car back from the tuning shop.

What I have done to "try" and fix:
- replaced slave cylinder
- bled clutch both cold and warm engine

 

have you replaced the master?

btw, it's vtec

 

Haha my bad, no I have not. Would this be on the firewall?

 

Also be sure you bleed all the air out of the lines. What brand is the clutch?

 

yes

 

Yes, I have bled all air out and old fluid (fluid is clear as it should be now). The clutch is a ClutchMaster from ebay... I know its nothing spectacular but I have bought these clutches before and have gotten 20k+ miles on them. Just have never had a lightweight flywheel. Ill check the Master and see if there are leaks...

Also, I should mention that the car is only half tuned, and from my understanding when the motor gets more broken in (over the last 1200 miles) the fuel, air, and overall tuned should be modified. Is this correct? It goes back into the shop today to get the tune finished. They didnt finish it the first time because the Tial wastegate was leaking boost so I had to have an O-ring replaced from a manu defect. I wanted to see if this was an issue as I was going to try and fix the problem before I bring it back in for the tune.

 

I would pull off the trans. It sounds like you have an issue with the flywheel or clutch as well as a bad master or slave cylinder.

 

If this were a clutch issue would the shop who built the motor, did the tune, and put the motor in the car be to blame? Again, the clutch has maybe 2000 miles on it.

 

Might I add it only makes the noise/pulse when motor is warm. Pulse in clutch pedal is only slight when motor is cold.