When at a complete stop, my car will SOMETIMES shudder and shake while the clutch pedal is being engaged. Sometimes it is very slight, and sometimes it can be VIOLENT. And sometimes it doesn't shake at all. The shake is similar to when you don't give enough gas and the car is about to stall, except much worse and sometimes its just enough to notice it. If its a slight shake I can usually power through it but if its a violent shake I have to push the pedal back to the floor, rev it and try again.

My cars an 03 with 26,0xx miles, could it be bad motor/tranny mounts? Clutch or flywheel problems? I really have no clue so any insight on this would be much appreciated! Thanks.

 

Usually it's caused by warped friction surfaces on the flywheel and on the pressure plate.

 

And the warp in those surfaces are caused by overheating the clutch and flywheel over and over. The clutch disc is likely badly worn and glazed from the heat. It will get worse over time and will eventually permanently damage the flywheel mating surface (if it hasn't already).

 

So what exactly are my options here.. new clutch and flywheel?

 

I just changed out my clutch. The throw out bearing started making a noise. I did it myself in my drive way Really wasn't as big a deal as I thought just make sure you Mark your old flywheel where it's at and transfer that to the new one so you don't have a problem putting the new one in. I didn't have to take out the right catalytic converter.just the rest of the muffler pipe to the drive shaft. One more thing if your doing the job on jack stands you will have to make sure the front is 24" high to just roll out the transmission on the transmission jack. I jacked up the front after I had the transmission off. They say the Top two bolts are hard to take off but I just laid on the engine from the front and used a long socket 1/2 to get em off. Runs like a champ.

 

First you need to confirm that it is the clutch. Does it do this when you slip it at about 2000 rpm or more?
My car does this a little bit, but only if I try to go at a low rpm with very little clutch slip......it was a lot worse. Now I have poly diff mounts and my engine/trans mounts are good. The clutch is not warped, but I think the dual mass flywheel is getting worn.

 

I want to say it usually only does it below 2000 rpm.

 

Just drove to school before, I realized it if I keep it below 1500 it's a hit or miss on how bad it vibrates but 75% of the time it'll vibrate atleast a little. Above 2000 it'll rarelyyyy vibrate at all.

 

My car did this for a little until I got used to shifting in it. My last car was a 2010 camaro SS and the clutch engaged at a different pedal height and with less gas. I was able to actually engage 2nd gear from a stop without issue in it. When I bought the Z I had to get used to how its clutch worked and for probably the 1st month of regular driving it did this. Sometimes to the point where it would shake the sh** out of me and my wife and we'd laugh. Now that I'm used to the clutch in the Z it happens only very rarely when I dont give enough gas or disengage the clutch to slowly or late. I bought my roadster Z last year, 2005 with 11,9XX miles from someone in MI so I do not believe my clutch was worn. Take her in and have it checked. Try disengaging the clutch with the pedal higher up with a little more gas.

 

That's exactly what I thought. A warped clutch will vibrate at any rpm.

You have a case of the "driveline jiggles". I'm still unsure if the dual mass flywheel plays a part in this, but since I changed my diff bushings the jiggles have gotten much better. I can still make it happen, usually when I'm not trying to, but the driveline has a lot of compliance on these cars and that's what happens.

 

A week ago I had 4.08 gears and whiteline diff bushings installed, from what I remember it has happened before the install but once in a blue moon. Gears have no whine so that's not the problem... or I think anyway?

 

Looks like the problem is you not being smooth enough. It still happens to ME occasionally when I am tired or worn out. What other cars did you come from? Before the Z, I had a 2003 Civic Si and before that was a 1990 Accord LX. Hondas have much smoother engaging clutches, but they do not have nearly the clamping force as the Z.

 

Changing the clutch may help a little, but I haven't gotten that far yet myself, so I can't be sure. I do know it's not from being warped, but it could be from hot spots on the flywheel/pressure plate.
Either way, the 350z's spongy mounts are allowing the problem to happen.

 

I actually learned on this car and I know its not from being unsmooth, Ive had my bucks and bogs haha and its not that

 

I don't know if the issue I had with mine will help but I had my clutch, flywheel, throw out bearing, master and slave cylinder all replaced at pep boys and they over torqued the pressure plate and bent it on install. Well after about a month of driving it would start to shimmy or shake when going from a stop unless I was just perfect with the pedals. If I gave more gas than necessary it would shudder pretty bad and on an incline it was really freaking bad.

Once I got the new pressure plate installed everything was back to normal.