I've been reading up on this problem and have found that in the 2007 350Zs they had a recall to replace the clutch slave. I have a 2006 and I think I may have the same problem.

Every now and then (the car has 82k on it, I've owned it since new and this has happened about 5 times to varying degrees) the clutch pedal will not return to the fully released up position when I take my foot of it. Once it stuck right to the floor and I had to pull it up by hand, then it was fine. The other times, it will come off the floor but not come all the way up. The spring pressure in the pedal assembly will prevent it from going the last few inches. I can pull it up with my toe and it'll pop back to the top.

The clutch grabs fine and I think it's got something to do with how the clutch slave cylinder comes into contact with the clutch release fork. I think the piston is not seating correctly on the clutch fork.

Is this the same problem that happens with the 2007 cars? Has anyone else had this problem? Can this be fixed or do I need to replace parts?

 

Clutch master needs a rebuild, been posted many times. My 05 had the same problem.

 

I changed the clutch fluid just by sucking it out of the reservoir, put in new fluid, pump clutch, repeat until it comes out clear and that fixed the same issue in my 06. Easy and cheap to do, might be worth a shot.

 

Many years of working on cars tells me that a fluid flush won't fix the problem. Since the problem is sporadic, it might just mask the issue for a little while only for it to reappear later. This certainly feels like a mechanical issue to me. If a hydraulic system gets air in it, the resulting problems will be consistent. For my pedal to go from absolutely fine to only coming up half way and then back to perfectly fine all of a sudden tells me that this isn't a bleeding problem.

I have inspected the clutch master cylinder and it is full of clean fluid and shows no sign of leaks.

 

Can you explain what is happening in the master cylinder to cause these symptoms?

 

My 05 with 49K did the exact same thing on the long trip home from the dealer. (Long Story)

I ended up having to put a clutch master cyl on it. It's extremely easy. Two nuts on the inside and the line on the outside. I bought mine from autohaus for something around 80 bucks. Picked up some Dot 5 brake fluid and it seems good to go.

They say to replace the slave with the master. However, my MC fixed the problem for now. I'm going to replace the slave anyway and a braided line.

 

Sediment, causes the piston to stick. You can just take it apart and clean it, but the rebuild kits are cheap, around $10 . Do the slave at the same time, same cheap price.

 

I know mine does this when i'm bleeding it, so i would have suggested the slave cylinder, but seems a bunch of people here did the master to fix it.

 

I did this as well.

EDIT: No I didn't! I did the proper method of flushing the old stuff right out of the bleeder valve on the slave cylinder until the new stuff came out nice and clean with no bubbles. My pedal has been flawless going on 8 months now.

My pedal would stick in traffic or really hot weather. Never happened since I flushed it with some Motul 5.1

 

Try bleeding it really well first. It's worked for quite a few people, including a couple in this thread. Use some good fluid like Motul or similar. If you want pricing on Motul or ATE fluid, let me know.

 

Common problem in OZ is heat, the hose at the MC is metal and as it goes down to the SC it's rubber. Here is where the problem is, it passes real close to the exhaust . If you are sitting in traffic on a hot day the fluid boils - pedal no return. Once you get some air flow it's ok. My fix here is Motul rbf 600 and a S/S hose and all is well in the land. I went one step further and fitted Earls fire proof hose for extra insulation.

 

Yep. And don't forget that once a fluid boils, it's compromised forever.

 

I changed the clutch fluid just by sucking it out of the reservoir

 

Just did the same on my 07, fixed the problem

 

yeah mine did it at the track once, did that fix and have never had the problem again luckily

 

so i put on the new ss hose and im having issues building pressure. can anyone throw mw a bone here?

 

07 Nismo here, had mine go out a few years back. Nissan took care of it under warranty. Had to replace the slave master cylinder. What pissed me off more than the part having to be replaced was the prix at the dealership who tried to claim it was because of abuse to the clutch rather than it being a recall issue. Mechanic went through and saw it was faulty and the guy was forced to do it under warranty. He probably felt dumb. But ever since the repair there has been a little "hop" in accelaration around the 1200 rpm range. Still havent been able to figure out what it is. Maybe mechanic at Nissan didn't put the transmission back together properly?

 

its typically the crappy master before the slave that goes out. easiest potential fix would be to flush the fluid i suppose.

then if the problem still occurs rebuild or replace the master. its pretty simple.

 

In all the cars I've had over the past 20 years (95% of them manual transmissions) I've never had a clutch master cylinder stick due to sediment build up and I've had some cars with 180k +. The fluid in these 350zs should be pretty clean even after many years without being changed. Fluid in the hydraulic clutch system isn't exposed to much if any heat so it won't go bad like fluid in the brake lines.

I have determined that the problem I was having was due to the clutch slave cylinder pin becoming unseated from the clutch fork. I'm really tempted to say that is the issue most people have when their clutch pedal starts sticking to the floor or only coming up part of the way. Of course there could be other causes but if your clutch hydraulic system has not been worked on since the car left the factory and the problem is sporadic, I bet you dinner at a steakhouse that it's the pin not sitting where it's supposed to on the fork.

I'm going to take mine apart in the next few weeks and then I'll do a write up of what I find.

 

^I wouldnt be so certain. The matter of a clutch not returning can be mutiple things, and the master on our cars have been known to fail. At 63k miles my clutch fluid was extremely clean. Did that stop the master from failing? There was no sediment in my master when i pulled it off. I replaced it anyway and that fixed my problem.