As some of you may know, I am a new , proud owner of an 04 Z with 50k miles on it. I came from owning 2 supercharged mustangs and this is my first Japanese built vehicle. I -was- skeptical.

Anyway, to the point. The 350Z clutches are spongy, but granted I am coming from a stage 4, I figured it was just me not being used to it.

All was going good up until today. Today when I started my car, I realized I have no first gear. I can shift into first, but... my clutch doesn't grab. I can let all the way off the clutch pedal and the car doesn't move in terms of speed nor RPM's, it just sits idle as if it was in neutral. Normally I would assume this to be a bad clutch. I worked at a shop for a while so, I decided to proceed with getting her moving. I went ahead and retried a few times, did some high rpm shots and got it moving and into first.

After driving all is just fine. Smooth shifts. Stop lights going back into 1st and cold stop = good grab, normal clutch actions. No high RPM slippage as you would expect from a bad clutch.

I get back home turn it off. Go to leave again - same issue. Once it is started and in first and moving all subsequent driving is fine. Going into first from a cold start = no go. Nor any other gear for that matter. It just sits idle.

Could this be my clutch going?

I am thinking about replacing it. I have heard some suggestions especially JWT but I am on a budget, the Z is a moneypit because it's a toy and I am conscious of that, but I am redoing the interior and thats a huge cost. So I am hoping not to spend a lot on the clutch. I have a qualified mechanic (where I worked) who will do all the work no charge, he owes me favors for loans.

As a result, I just need to buy a clutch. Budget is 700ish. I want to replace the flywheel too (I think thats recommended on Z's, no?)

I found this kit: http://www.conceptzperformance.com/C...&Car_Type=350Z

has anyone got any feedback?

 

That's a pretty strange issue...however, I would think if it was your clutch giving you problems it would be present in all gears not just one. Maybe it's some type of synchro issue? Typically that causes griding 3rd and 5th gear shifts...but I suppose if the 1st gear synchro was just about completely gone that could happen...

Do you hear anything audible when trying to engage in 1st when cold? Usually you can hear the flywheel chatter note change just by pressing the clutch pedal in and out. If you sit at idle, push the clutch in, and don't hear any type of audible note change under your car it probably is the clutch/flywheel.

Hopefully we can help you diagnose this...I'm just shooting ideas out there

 

Hi there,

Not hearing a lot of noise, there is some chatter. I want to blame by clutch on going but its weird that I get no slippage if I am already moving (not cold start), no fails, very properly gripping, no high rpm slippage either.

Super strange issue, I plan to take it to a shop, but I am currently in Central America and they often poorly diagnose simple issue, slightly concerned about how well they would diagnose a real issue.

 

This is kind of a misleading and important point that is buried in your post given your thread title. I would say clutch and while your in there, replace the throw out bearing as well.

 

My friends 98 mustang had this sort of problem(though we never actually tried to drive it) It would barely grab unless you redlined it. Upon taking apart the tranny the stage 1 clutch was fine, but the flywheel had hairline cracks everywhere and was warped badly.

 

unfortunately I dont have a good answer for you. I hope the members of this forum can point you in the right direction.

On a side note though, you said you feel the clutch is "spongy." You may want to look into a adjustable clutch assembly such as RJM. The factory clutch has a nasty spring mechanism that gives false engagement feel.

GL with this strange problem!

 

For a clutch you can get the JWT clutch with LE flywheel, ss clutch line, tob, and pilot bushing for 775 shipped from a vendor on here. It is a absolutely great clutch.

I had this issue on my old SR. The teeth on my clutch disk were almost gone. Not sure if that helps, also not sure how it happened I figured it was because I cheaper out on a spec. Got a exedy street clutch for it and never had a issue again.

 

Thank you all for the replies. I will probably replace the assembly for the "spongy feel" as mentioned above - great tip.

This form is honestly awesome. I am thinking flywheel could be an issue vs the actual clutch due to the weird symptoms.

Unfortunately, there is no way to know without dropping the tranny and to be hones, that's not going to be cheap. I don't have the tools or an adequate lift at home to do it myself, so it will have to be shopped. I have a friend who can do it but he is backlogged on work so he said I gotta wait, and I am dying without my Z.

I am going to shop around the forms, find a clutch kit and get it sent to me and will just change it. If I have to drop the tranny anyway, why not go ahead and be prepared to replace everything.

Thanks I will update when I get a result.

 

My clutch does not feel even close to spongy. I would first change your clutch and flywheel then see how it feels.

I know you're used to rock solid mustang clutches, but once you put a new clutch on the Z, welcome to the world of how a sports car clutch should feel.

 

A JWT clutch and lightweight flywheel combo is $775 at Z1 and is the most common (and probably best regarded) as far as entry-level clutches go. I have them myself and they're nice.

 

You mentioned that when things were working normally, the clutch engages fine does not slip when driving. In this case I don’t think you should be looking at replacing the clutch and associated parts, but instead look into the action of the master and slave cylinders.

The master cylinder is a simple little creature, at the end of its piston stroke is a plain small hole (no valves or other mechanism). Fluid is forced out and into the slave cylinder, which is pretty much just a master cylinder in reverse. When you release the clutch pedal the pressure plate spring forces the fluid out of the slave cylinder and back into the master cylinder. If a small piece of dirt or rubber from one of the piston plunger seals is floating around loose in the clutch line it could easily act as a flap preventing the fluid from re-entering the master cylinder, this would keep the clutch from re-engaging even with your foot off of the pedal.

After about 8 years of daily driving the neighbor who serviced my car suggested we change out all the fluids. The clutch fluid was so dirty and full of crap, he decided to remove the master cylinder and give it a good cleaning. It was an easy job that didn’t much time, but he said it was worth it because he had seen loose crap cause problems similar to what you are experiencing.

As you know diagnosing car repairs over the Internet is difficult, but maybe look into the master/slave as a cause of this problem.

 

+1 on replacing/cleaning master & slave cylinders. My pedal started not returning all the way after a shift, and it was a dying master cyl. I decided to get a SS clutch line and slave cylinder while I was at it because they're so cheap. Get a master and slave cylinder from RockAuto.com. Super cheap and you could probably do both in your driveway. Way less involved than a clutch. You mainly need the correct tools for bleeding the clutch, which is the biggest pain of the whole install.

 

Thank you x2 to the last 2 replies. To be honest, I want to just replace the clutch but the same money a clutch will cost me down here (Central America) could do a lot more mods like an LSD. Anyway, if I can avoid it for now, I'd like to. I find it funny the clutch grabbed so well and then magically stopped. Not typical of a bad clutch which slowly slips.

Totally didnt think of master/slave cylinder. Tomorrow it goes to the shop and I will ask them to check that first. If flushing fluids/changing cylinders works, it is much easier than buying a new clutch. I want to change my clutch but down the road, if it's not dead yet why do it now. I will go JWT when I do (thanks for the recommend, 775 is now bad at all, labor is around 200 USD here for a change).

I could check the cylinders myself, I worked at a shop a while but my job leaves me -1 free time, so not likely. Hoping to get the shop to do it.

I will update. Thanks all for helping out a new Z owner, it means a lot, seriously.

 

this sounds more like a transmission issue rather than clutch.. synchro's maybe

 

I was thinking more about this and I realized that it's most likely not the master/slave cylinders. Typically, when they start to die, the clutch will not disengage. If the seals start leaking, then you will not have any presure in the system. That means you would not be able to get it into gear without severely grinding it. Or at the very least, the car would lurch forward with the clutch pressed in. Whatever the issue is, sounds like the car could become 100% undriveable at any instant.

 

Master/slave cylinder is my bet.

 

^ agreed.

 

Hello All,

So I am back from the dead!

According to my mechanic, it's the master and slave cylinders and the flywheel is in bad shape. The clutch is not. He does not know how the flywheel got screwed up but he says it is.

Anyway, I decided, while it's ripped apart and I am stuck driving an SUV anyway, I might as well take the money I planned on cosmetic crap and invest it in the actual mechanical function of the car first.

I plan to change out the clutch and everything related.

I plan to buy the kit from Concept Z with the JWT clutch, flywheel, clutch cable, etc.

My question would be, what else should I change out while I am doing this?

 

I think it was mainly a problem with the '03 clutch pivot ***** breaking, but it's cheap insurance to get this: http://www.z1motorsports.com/350_g35...oducts_id=6517
Maybe it's overkill, but I had my OEM pivot ball break on me at 122k miles...and really I think it was cracked long before I noticed.

 

Pivot Ball, TOB, Slave, SS clutch line, LW Flywheel, ARP flywheel bolts, Even maybe a new sleeve/fork. I went ahead and replaced all of that when I changed my clutch out just to be safe.