Notices
924/931/944/951/968 Forum Porsche 924, 924S, 931, 944, 944S, 944S2, 951, and 968 discussion, how-to guides, and technical help. (1976-1995)
Sponsored by:
Sponsored by:

Clutch pedal half-depressed after turning cruise control off, but can be pulled back?

Thread Tools
 
Search this Thread
 
Old 11-24-2012 | 02:20 AM
  #1  
Sentinelist's Avatar
Sentinelist
Thread Starter
Pro
 
Joined: Jun 2010
Posts: 733
Likes: 0
From: North Dallas, TX
Question Clutch pedal half-depressed after turning cruise control off, but can be pulled back?

I just noticed that occassionally when I 'cancel' the cruise control (maybe by hitting the brake, not with the stalk), the clutch pedal makes a 'WUNK!' sound and depresses toward the floor about 50%. Weird feeling to go to change gears and the clutch isn't there! Oh, there it is... wth... but it does still work fine. Obviously with half the clutch travel, so I hope it's not wearing out anything (I noticed this and parked it back home a mile later). Interestingly, the clutch pedal does pull back into position with my foot and is perfectly fine after that. Do I have a bad clutch switch or something? Of note, I just swapped in a working cruise module and this is the second time I've ever used/tested it, so I know it's related to that (putting the finishing touches on this car).

Search didn't turn up anything except an interesting thread in the 996 area about a damper spring that they all take out. I've only looked under the dash enough so far to notice I indeed have a switch or some sort of sensor with wires at the top of the clutch pedal, but would welcome your thoughts.
Old 11-24-2012 | 02:39 AM
  #2  
Butters944's Avatar
Butters944
Today I got
My Custom Title
Rennlist Member
 
Joined: May 2011
Posts: 4,857
Likes: 0
From: Las Cruces NM (NMSU) / Fountain Hills AZ (home)
Default

My clutch does the same thing but I don't have a cruise control. Sometimes when I take my foot off the clutch it stays at that halfway position (kinda a natural stopping point, which I think is before any wear-point). I've got in the habit of pulling it up with my foot each time but have been thinking, what if I can rig it up to always stay at that low position..? Because racecar..?

I thought I was the only one who had awkward clutch issues.

FWIW I adjusted the tension in the spring at the pedal to make the wear point higher and have the spring pull it up better. It helped for a week, but ever since has still acted up off and on (like 30% of my shifts).
Old 11-24-2012 | 03:24 AM
  #3  
Dr944S2's Avatar
Dr944S2
Instructor
 
Joined: Feb 2010
Posts: 109
Likes: 34
Default

Hi,

what about bleeding the clutch system:

https://www.youtube.com/watch?v=cM3w-JBMbdE

Have also a look at the firewall where the master cylinder is fixed. I saw several times that the firewall has been broken there.

regards,

Jürgen
Old 11-24-2012 | 03:52 AM
  #4  
AlphaOmegaPower's Avatar
AlphaOmegaPower
Pro
 
Joined: Oct 2011
Posts: 521
Likes: 2
From: Tennessee
Default

Originally Posted by Sentinelist
I just noticed that occassionally when I 'cancel' the cruise control (maybe by hitting the brake, not with the stalk), the clutch pedal makes a 'WUNK!' sound and depresses toward the floor about 50%. Weird feeling to go to change gears and the clutch isn't there! Oh, there it is... wth... but it does still work fine. Obviously with half the clutch travel, so I hope it's not wearing out anything (I noticed this and parked it back home a mile later). Interestingly, the clutch pedal does pull back into position with my foot and is perfectly fine after that. Do I have a bad clutch switch or something? Of note, I just swapped in a working cruise module and this is the second time I've ever used/tested it, so I know it's related to that (putting the finishing touches on this car).

Search didn't turn up anything except an interesting thread in the 996 area about a damper spring that they all take out. I've only looked under the dash enough so far to notice I indeed have a switch or some sort of sensor with wires at the top of the clutch pedal, but would welcome your thoughts.
Have a Slave and master cylinder ready. Confused me for a while and let it go. Almost caused a big problem. Also the clutch hose. My advice is change it all asap and bleed. I was going down a bridge when my clutch hydraulics went out.
Old 11-24-2012 | 04:25 AM
  #5  
Sentinelist's Avatar
Sentinelist
Thread Starter
Pro
 
Joined: Jun 2010
Posts: 733
Likes: 0
From: North Dallas, TX
Default

Sounds like this is on the right track... that service hasn't been done since the late-90s according to my records. Looking at this on Clark's now. What's the real-world level of do-ability?
Old 11-24-2012 | 04:41 AM
  #6  
AlphaOmegaPower's Avatar
AlphaOmegaPower
Pro
 
Joined: Oct 2011
Posts: 521
Likes: 2
From: Tennessee
Default

Originally Posted by Sentinelist
Sounds like this is on the right track... that service hasn't been done since the late-90s according to my records. Looking at this on Clark's now. What's the real-world level of do-ability?
Very easy. Was my first job to start working on mine. LOT easier if you are a smaller person....I am not.

Have everything Clarks tells you to get and as far as tools and it will be no issue. Under the dash will cause the most issues. Also might help to have one of those magnetic extenders in case you drop a nut off the master cylinder. Worry about the master first. Then the slave. Helps to have a Power bleeder. Also was the time i ordered a stainless steel line to the slave cylinder.

To get to the slave you have to unhook the battery the unbolt the starter from under the car. Nothing hard about it. Just 2 19 mm bolts if I remember. then the wires. all is straight forward. Please makes sure car is up and stable. Not difficult. Master cylinder will be the challenge but can take hour and 30 MAX to pull one off and install another one WITH the right tools.
Old 11-24-2012 | 08:56 AM
  #7  
968 GUY's Avatar
968 GUY
Racer
 
Joined: Sep 2009
Posts: 397
Likes: 1
From: Ga.
Default

If you are taller or big around, one trick is to remove the seat. 6 bolts. You have to move the seat back and forth to get to them but no big deal, make sure you remember which one goes where.
Also replace both the high pressure hose between the cylinders, and the hose from the res to master cyl. Good insurance for not having to redo something.
Another trick is to hook up the high pressure hose to the slave before bolting it up. You can feed the slave down frmo the engine compartment. If you are really good, you can have both cylinders hooked up to the hose and do a bench bleed which may make things a bit easier for the main bleeding exercise.
Check for firewall cracking and replace the gasket at the master cyl.
Old 11-24-2012 | 12:12 PM
  #8  
Sentinelist's Avatar
Sentinelist
Thread Starter
Pro
 
Joined: Jun 2010
Posts: 733
Likes: 0
From: North Dallas, TX
Default

Thanks for the tips and tricks, guys. Is there more confidence than not that this is the issue? Want to make sure before I start ordering parts (Monday).

I can probably do the work myself- I'm tall but thin. May take the seat out.
Old 11-24-2012 | 09:31 PM
  #9  
AlphaOmegaPower's Avatar
AlphaOmegaPower
Pro
 
Joined: Oct 2011
Posts: 521
Likes: 2
From: Tennessee
Default

Originally Posted by Sentinelist
Thanks for the tips and tricks, guys. Is there more confidence than not that this is the issue? Want to make sure before I start ordering parts (Monday).

I can probably do the work myself- I'm tall but thin. May take the seat out.
This IS your issue. Or your reservoir is leaking....

Change the Master AND slave or risk going back in. This one issue had my Turbo down for 3 months due to where it happened at. Do not let my hardships and experience with this go to waste lol
Old 11-24-2012 | 11:36 PM
  #10  
TexasRider's Avatar
TexasRider
Late Porkchops
Rennlist Member
 
Joined: Mar 2010
Posts: 12,573
Likes: 97
From: Houston, Texas USA
Default

They beat me to it. I was going to say Slave or Master.

You could always replace the slave and see. But it might be better to knock them both out.
Old 11-25-2012 | 12:49 AM
  #11  
Sentinelist's Avatar
Sentinelist
Thread Starter
Pro
 
Joined: Jun 2010
Posts: 733
Likes: 0
From: North Dallas, TX
Default

Ok thanks, guys. Yeah I'm more of the school of thought to just knock both of them out to be sure. Chalk one (or two) up for the records binder. If this wasn't the problem I will report back!
Old 11-25-2012 | 10:50 PM
  #12  
Sentinelist's Avatar
Sentinelist
Thread Starter
Pro
 
Joined: Jun 2010
Posts: 733
Likes: 0
From: North Dallas, TX
Default

Update: with normal clutch pedal feel after I 'pulled' the pedal back a couple days ago, I decided to take it out for a progressively spirited drive around a local backroad this evening as I quickly regained confidence in it. At least 100 clutch engagements over the course of 30 minutes, if not double. Flawless performance, no issues. I didn't try it again, but I think the issue is only when disabling the cruise control (again, which I just installed last week, and never saw this problem before).

I don't doubt there may still be an issue with the master/slave cylinder, but it's only apparent when the cruise is used. I still wouldn't hesitate to jump in and drive cross-country as it is now. And for anyone very closely following along lately, I am planning to sell the car. I literally had the write-up done and was about to go take photos of the thing when this happened once, so now I'm wondering if I have another repair it's conveniently got me captive for at the worst timing that I should bite the bullet and take care of, or note a FYI on this part for the next buyer. Argh!
Old 11-26-2012 | 01:40 AM
  #13  
944Time's Avatar
944Time
Instructor
 
Joined: Apr 2005
Posts: 229
Likes: 10
Default

On the later cars you don't have to go under the dashboard.
Just pull up the fuse box.
More Info

Old 11-26-2012 | 11:23 AM
  #14  
Sentinelist's Avatar
Sentinelist
Thread Starter
Pro
 
Joined: Jun 2010
Posts: 733
Likes: 0
From: North Dallas, TX
Default

Drove it to work this morning as well- business as usual...

Interesting about the fuse box trick though.
Old 11-26-2012 | 07:42 PM
  #15  
darrengj's Avatar
darrengj
AutoX
 
Joined: Apr 2010
Posts: 13
Likes: 0
From: Cape Coral, FL
Default

That fuse panel trick would make things a little easier. I am doing the same job. I didn't even think of being able to disconnect the clutch pedal without laying upside down. I am not home to check, so does anyone know if that would work on a 85.5? The article states it does work on a 86.

Thanks,
Darren


Quick Reply: Clutch pedal half-depressed after turning cruise control off, but can be pulled back?



All times are GMT -3. The time now is 08:23 PM.