Sticky Clutch Pedal

[Gavla]

If it is the pressure plate - isn't it worth upgrading to an aftermarket clutch like LOBA? I'm in two minds to go OEM or look at alternative as mine is exhibiting these symptoms now under spirited driving

[Surrey Sam]

Or perhaps approach someone like AP Racing for a redesigned/upgraded pressure plate assembly. It could be worth their while if every B7 RS4 is going to experience this over the course of the cars lifetime; I certainly wouldn't want to spend ££££'s on fitting an OEM replacement only to have the problem raise its head again further down the line.

I might draft up an email and fire it over to their tech team.

[Gavla]

That's pretty much my thoughts Sam

I would like to pursue this also - I might drop MRC a line to see what they recommend as it seems to be quite a few on here are suffering with this.

[Coaster]

Hrm, interesting. If I'm reading this right, you had every aspect of the clutch hydraulics and assembly replaced and still experienced the problem?

Yes you are. As far as I was aware and had been told by the dealer all elements of the clutch had been replaced. However, I wouldn't be surprised if they had not done as they had said as they seemed to have very little understanding of the issue.

[Surrey Sam]

That's pretty much my thoughts Sam

I would like to pursue this also - I might drop MRC a line to see what they recommend as it seems to be quite a few on here are suffering with this.

Gav, would be interesting to see what the MRC guys thoughts are on the problem, as I'm sure they've had a few cars in with the problem over the years.

[Wavey Dynamicist]

That's pretty much my thoughts Sam

I would like to pursue this also - I might drop MRC a line to see what they recommend as it seems to be quite a few on here are suffering with this.

Gav, would be interesting to see what the MRC guys thoughts are on the problem, as I'm sure they've had a few cars in with the problem over the years.

If you do, be sure to let us know.. I'm still leaning on the exhaust manifold issue, it's the only thing that remains constant among the various clutch component replacements people have had..

I was considering speaking to someone at Audi HQ about the issue, there's no way they haven't heard of the issue..

[sakimano]

Thoughts point to the pressure plate of the clutch. Also a problem found on the JHM clutch which had all different components except for the pressure plate.

On the old one yes

On the new JHM 1r and 5r, all re-engineered. No more SAC and OEM pressure plate has been ditched. New plate was developed with the new clutch for their supercharger kit.

[irishmike]

It would be interesting to see what Audi have to say on it.
I mentioned to the local dealer, but as RS4's are quite uncommon here they had never heard of the issue.

On mine they are going to change the fluid first ad check the return hose, if that does not work they will work up to the master/slave cylinders and then the clutch itself.
So glad i bought it off a garage with a warranty!

[irishmike]

Just an update on this.
Dropped back to the dealer yesterday.
They are going to do a pressure bleed on the system, if that makes no difference they will take out the clutch and examine it.
Fingers Crossed....

[ArthurPE]

there is a TSB that says to replace the master to slave hose
it did not fix mine (in fact I had it wrapped with heat shield tubing when the dealer did the work)
the slave was replaced at the same time

my guess is the throw-out bearing guide bushing binds when hot and gets gummed up with clutch debris/dust
after being worked a few time it gets cleaned off and cools down
before I sold mine I thought about washing the housing out with brake cleaner to see if it helped

it's a weird problem, the clutch still works when stuck?
I thought it was the pedal spring return mechanism, it's got a set-up that has an articulated turn over point to ease operation and seems to get stuck after the leverage point
it has a helper spring to help it get back over that point, perhaps not strong enough under some conditions?

[Gavla]

I had some feedback from Doug on this albeit a bit fragmented. He has this thread link so hopefully he'll contribute further.

Here's some of the feedback.

"Pressure plates are light and the variation in tolerances means some are just a bit too weak to pull back off the disc(when hot). The hydraulic line has helped in some but that is usually the ones that have been bent too much or just bleeding the clutch helps."

"You can also get play in the flywheel and it doesn't help the issue - play can cause gearbox casing to break so change that before it does that."

"Sometimes bleeding or replacing the line can help when it is really marginal."

I have a quote for a LOBA Single Mass 550NM and will eventually go down this route as it upgrades these parts and what I've read so far seems to be reliable.

[Wavey Dynamicist]

there is a TSB that says to replace the master to slave hose
it did not fix mine (in fact I had it wrapped with heat shield tubing when the dealer did the work)
the slave was replaced at the same time

my guess is the throw-out bearing guide bushing binds when hot and gets gummed up with clutch debris/dust
after being worked a few time it gets cleaned off and cools down
before I sold mine I thought about washing the housing out with brake cleaner to see if it helped

it's a weird problem, the clutch still works when stuck?
I thought it was the pedal spring return mechanism, it's got a set-up that has an articulated turn over point to ease operation and seems to get stuck after the leverage point
it has a helper spring to help it get back over that point, perhaps not strong enough under some conditions?

Did you also get the master cylinder heat shielded?

[irishmike]

there is a TSB that says to replace the master to slave hose

Do you have any more info on that?
Not been done on mine and Garage weren't aware of it...

[ArthurPE]

there is a TSB that says to replace the master to slave hose
it did not fix mine (in fact I had it wrapped with heat shield tubing when the dealer did the work)
the slave was replaced at the same time

my guess is the throw-out bearing guide bushing binds when hot and gets gummed up with clutch debris/dust
after being worked a few time it gets cleaned off and cools down
before I sold mine I thought about washing the housing out with brake cleaner to see if it helped

it's a weird problem, the clutch still works when stuck?
I thought it was the pedal spring return mechanism, it's got a set-up that has an articulated turn over point to ease operation and seems to get stuck after the leverage point
it has a helper spring to help it get back over that point, perhaps not strong enough under some conditions?

Did you also get the master cylinder heat shielded?

no, it's a good distance (relatively speaking) from the headers

I'm split betwen the bearing binding on the bushing and the pedal return mechanism

in the US some vette guys were having the same problem and they removed the clutch helper spring and it supposedly fixed it

[ArthurPE]

there is a TSB that says to replace the master to slave hose

Do you have any more info on that?
Not been done on mine and Garage weren't aware of it...

I'll look but when I sold my car all the records went with it
Audi replaced mine and the TSB no. was probably on the service slip

it will do it when stone cold
start the car up after sitting overnight: rev the engine to 6-7k a few times, it will stick

not the RS4 specific, but I think it's the same for all B7

Vehicle: 2009 Audi A4
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Nature of Defect: POWER TRAIN:CLUTCH ASSEMBLY
Bulletin Number: TSB-30-11-10
Bulletin Date: Dec 2011
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Summary:
AUDI: CERTAIN MODEL YEAR VEHICLES MAY EXPERIENCE A CONDITION WITH THE CLUTCH MALFUNCTIONING, BURNT SMELL OR NOT RETURNING TO ORIGINAL POSITION. ( NHTSA ITEM NUMBER - 10043275 )