Clutch Dead Zone

[R490]

Today vavJETTAw36 and I (mostly him) replaced the clutch master on my car.

After doing so, we noticed a dead zone in the pedal travel. This was there before as well, I really can’t remember it not being there.

Car has an RS4 clutch and an unknown flywheel.

Any thoughts? We compared it to his S4 and his buddies A4, and this was the largest. The car drives great and the clutch engages fine.

[LJS]

That's usually and indication of too much gap between the TOB face and the pressure plate fingers....
The cause of that is either a worn TOB face or aging pressure plate or a combination of both.
I don't know what the AUDI spec is for the gap between the TOB and clutch pressure plate fingers nor can I find that data...
Based on experience with other hydraulic clutch mechanisms on other vehicles I would GUESS that this gap is very small---several thousands on an inch.
As an example---When I installed a hydraulic system to my old FOX chassis 5.0 Capri RS this gap was set at 0.010
The main issue here is that to inspect things you have to drop the tranny....
UGH!!!!!!
are you hearing any noise when the clutch is out that disappears when you engage the clutch?????
That would be an indication of a worn TOB....
BTW- on our S4 there are NO adjustments available to correct this.
Just thought of something---try bleeding your clutch slave to see if that makes a difference....

[R490]

No noise and it drives great, bled today too

[LJS]

ok- it's a gap issue....
FWIW- I'd run with it until it got worst

[R490]

Gotcha, thanks!

We were brainstorming about extending the piston to get rid of the dead spot, until it can be dropped and repaired.

[LJS]

sounds like a plan---
BTW- when you do get around to dropping the tranny be sure to check the slave cylinder rod to insure both plastic ends are intact....
Thought of something else--
Be sure to check the spring clamp and pivot on the bottom of the TOB fork