RS4 Clutch feels like it has a "gap" in engagement

B6/7 S4/RS4
#1

I’ve been enjoying the hell out of my RS4. Hands down best car I’ve owned. I’m pretty convinced that I’ll never want to get rid of it.

I’ve been reading about clutch wear - on here and a variety of other forums and haven’t found anything for what I’m experiencing. Background on the car: 2007, 65k on the odom - I’ve only had it for a few months now.

The best way i can explain it is that the clutch feels like it has a “gap” close to the top of the release point. This is a new symptom that has only been present for a few weeks now. Before the clutch release was pretty smooth. The clutch starts to engage pretty close to the floor (id say a 1/4 to 1/2 out). the pedal feels the same stiffness throughout the release. at the 3/4 or so point it feels like it looses engagement and then catches again right after that. It is very noticeable in 1st and 2nd and this happens primarily when doing slow deliberate clutch release (like in traffic). The release isn’t smooth. If I’m more aggressive in release (faster release) , I don’t feel it as much, but you can still tell its there. I can feel it a bit less in each progressive gear and at 5th and 6th you don’t even notice it.

my driving is typically spirited, but no hard launches - just the typical pulling away quickly - but not dropping the clutch @ 6k and launching.

My best guess is that I need a new clutch and so I’m leaning toward an APR setup with a LWFW.

thoughts?

#2

APR?? Are you a troll?

They don’t make an RS4 clutch and they ran the JHM setup on their 1740 1/4 mile car

#3

got my initials messed up. Not APR. JHM. not trolling… just a typo.

#4

Haha, ok.

You might want to just try changing out the slave if you can, but the clutch could be worn @65k depending on its past.

#5

try this:

take care on the road
go 20 or 30 mph
put in 6th gear
floor it

Any RPM spikes? Or do RPMs climb in a slow, steady increase (it will lug a bit and be down in the 1000 RPM range, but that’s ok for the experiement)

welcome to AR. Please post some pics of your car somewhere. What colour is it? Where are you located?

#6

The dual mass flywheel can feel unpredictable in its engagement. Based on how it works, there is a little “slop,” especially if you are used to a very precise clutch.

I know this is subjective, but bear with me… my Subaru STi has an aftermarket heavy duty clutch, and a solid LWFW. This system feels razor sharp in terms of engagement point precision. I know exactly where, and how much engagement will happen, and find it very easy to obtain 100% predictable response from the car.

By way of comparison, I have learned to accept a “range” of engagement with the RS4. This “range” isn’t very large, but is just enough to be a source of annoyance. My next clutch will be a JHM unit with single mass LWFW.

#7

I’ve been b itching about this exact thing since I bought my car. My solution is get rid of the dual mass self adjusting bullshit. There are a lot of threads on ppl complaining about this issue and I found one where a guy called audi and they told him it was a design flaw and could not be fixed.

#8

This sounds different guys. Sounds like it is slipping to me. Read his description… He says it engages, then disengages, then re engages

That is nowt to do with the sac.

#9

tried the 6th gear test @ 30mph - tossed it in 6th and floored it - no slipping. it did lug, but it just slowly climbed out of it without issue.

after doing several of these, the clutch engagement did feel better strangely, but only for a little while…

when I had an E46 M3 w/ SMG one thing that was common to do when your clutch started acting wonky was to unplug the battery from the car for 45 minutes. that would cause the system to reset and the clutch adaptation would reset back to default. That would often clear the issue (car bucking in 1st/2nd gear). is there anything through VCDS that you could use to do something like that?

#10

It’s good that you don’t have any slipping.

But your way off base with the SMG comparison. Our clutches are completely mechanical/hydraulic. Nothing at all can be reset/adapted in VCDS.
You’re either experiencing issues with the stock SAC system or possibly the slave cylinder IMO.

Most VW/AUDI vehicles have both dual mass flywheels and pressure plates with SAC (Self-adjusting clutch) system. This is nice for most of the platforms where comfortable driving is a requirement, but it isn’t exactly a great thing for a car geared toward performance.

To help you out, here is a short explanation: (I apologize if you already know this stuff, but it may help others)
-The dual-mass flywheel is basically a 2-piece springed flywheel. The purpose for this design is to absorb some of the drivetrain shock during clutch engagement, this is especially nice when most Audis are 4000lb+ AWD sedans/Avants.
-We also have a hydraulic clutch vs cable clutch, which takes a little bit of the “feel” away from the driver, but a cable clutch configuration would suck with an upgraded PP with more clamping force. Using hydraulics make the clutch pedal much easier to press and won’t cause you to have an awkwardly muscular left leg…haha
-I think when you combine a dual-mass FW and a hydraulic clutch system it will take a lot of the “feeling” away from the driver when it comes to engagement. But it will be more comfortable from a daily driven aspect compared to a single-mass FW and/or cable clutch system.

-The advantages of the SAC system are below. It is also a nice feature for comfortability, but companies like JHM have found that it may be a failure point of the OEM pressure plate.
http://www.audiworld.com/tech/eng86.shtml (Good read/explanation)

[quote]SAC = Self Adjusting Clutch. This is a wedge mechanism in the pressure plate that over time & clutch wear, will adjust itself to keep the engagement point of the clutch at the same point. More importantly, it keeps the holding force consistant, but that’s not what the driver really relates to most of the time.
[/quote]
Dual-mass Flywheel

http://www.sachsperformance.com/templates/sperformance13/img/products/inhalt_sachs_zms01_en.jpg

SAC system are the springs around the PP diaphram fingers

http://www.audiworld.com/tech/pics/eng86_dscn7029.jpg

#11

thanks for the explanation - I love to learn about the car - I’m certainly no expert. I leave the difficult jobs to people who know what they hell they are doing, but I’m willing to try some stuff myself.

#12

Dual-mass Flywheel

http://www.sachsperformance.com/templates/sperformance13/img/products/inhalt_sachs_zms01_en.jpg

SAC system are the springs around the PP diaphram fingers

http://www.audiworld.com/tech/pics/eng86_dscn7029.jpg
[/quote]
Euro you should make this a thread take out the link to AW and add your thoughts in place.

#13

Will do Justin, I should also have a JHM 3R install DIY coming soon. I may not go into every step in detail, but I’m going to hit the important things like proper flywheel and pressure plate installation.

I had a failure this weekend, pretty positive the stock pressure plate gave up the ghost.

#14

Damn that sucks. It would be hard to get 500 miles in by time.

#15

Yeah man, I was about to text you. It may be after the New Year until I can play again. I’m excited to upgrade though. I had ZERO issues…no slipping…never had the pedal stick during high RPM shifting…so it kind of suck that is just shit the bed on me. Popped my tow truck cherry…31 years and never needed a tow, I’ve been lucky.

#16

we were just talking about how your clutch was good over on az, shoulda knocked on wood bro. any reason your choosing the 3r over thr 5r?

#17

Well you can always come out and take video for me Euro. A video from the stands would be good.

Badtoyz, the 3R is a good compromise for everything up to probably a stage one JHM SC kit. The RS4 JHM stage 2 SC probably needs the 5R in the long term.

#18

Well come on Jimmy… Not all bad news. Silver lining alert: means my stock rs4 record is safe!