Rattle when clutch is out, no rattle when clutch is pushed in
 

The thread title says it all. Whats going on?

Heat sheild is loose.



/

I thought this was more indicative of a flywheel issue. I have it too, and have not properly diagnosed it, so this is just my .02

I'm hoping it's a simple solution. Any other thoughts.

I have this, learned from a couple of mechanics it is normal. If it is loud may want to have someone check it out who you trust. If it's not loud I wouldnt worry about it.

Oh and regarding fatmike's comments about heat shields - loose shields can cause some odd racket and are easy to tighten with a 10mm socket. The bolts are kind of odd, and if rusted can be replaced with some stainless fasteners.

best of luck.

How would you determine if it's too loud?

When warm, mine sounds kind of diesel-like. Hard to describe. A "clattering" noise is the best I can describe it. Fairly loud when I pull into the garage with the top down, and actuate the clutch to hear the difference.

How does the clutch/engagement feel OP? Mine's kind of clunky and almost feels warped when I slip the clutch into an idle roll. Low power/low speed shifts are pretty harsh. This may be a characteristic of the car, I don't know. I've been attributing it to something to do with the dual mass flywheel.

My obvious concern with the car is the IMS. With that said I don't think there is anyway this is IMS related since it has to do with the clutch being pressed in and let out. IMS would be constant. Correct me if im wrong.

Clutch feels good.

Don't by chance have a light weight flywheel, do you? They make a lot of noise like you are describing.

That is normally a sign of a worn clutch release bearing , but could be something ancillary (bolt on) rather than mechanical (moving) ...
As an experiment , try it with the AIRCON on and off ... Any difference ?
Try it with revs held around 1200 .. Any difference ?

Did some more "testing" today. Started the car cold. No rattle at all. Drove the car, got it up to temp and the rattle came back but not as loud as it was last night. Any new thoughts?

Not that I am aware of. I am 4th or 5th owner. Car only has 47k miles on it so as far I am aware its the orginal clutch.

Sounds like you are most concerned about the IMS - I seriously doubt this is a symptom of IMS.

This topic is interesting for me because I went through the same thing in March - bought my 986S in January and listened for every little sound, paranoid about IMS failure. Sometimes I would hear a new sound and go straight to 'IT MUST BE THE IMS -OH NO!!!' and realize I just had the passenger window down etc etc.

One day I pulled into to garage and let the car idle in neutral when I heard the rattle - and I thought that was the big one. Rattle was not loud, just noticeable in the garage.

Called the independent who had done all the work. He sounded slightly amused (so many of us freak out about the IMS) and had me push clutch in and out with motor running to see how it affected sound. It behaved just like you describe. He said it is perfectly normal and maybe the clutch needed servicing, but his advice was to drive it and not worry about it.

After that I decided to go ahead and get the IMS replaced so I could not worry about it and just enjoy the car. I had IMS and RMS replaced, new clutch and oil changed for $2,500. Now I dont worry about any sounds from the engine and had already planned for this expense as part of buying the car. Purchase prices are down low enough to go ahead and factor in IMS cost. Also I plan to keep the car as a 3rd car for fun so the investment will pay off over time.

You may want to consider doing the same thing - bite the bullet for the IMS and enjoy the car.

Hope this helps.

Gary

Most likely either a worn throw out bearing, or a weak input shaft bearing on the gearbox.

This helps a lot. I just bought the car last night and inspected and listened to the car thorughly before buying. The second I get home and pull into the drive way this rattle occurs. Already budgeted for the IMS and plan to have it done in the next 2 weeks. Just wanted to reach out to the forum and make sure this wasnt a costly sounding rattle or something to be very concerned with.

Just make sure they replace the throw-out bearing when installing the new clutch.

Brad

have the mechanic listen before he tears it apart and tell him to make sure it's not there after he assembles it- re: JFP's comment. Probably a bearing that's just starting to go ( only when hot) and that's why the car was sold. That's one good thing about getting an IMS bearing replaced- YOU GET A WHOLE BUNCH 'O PARTS PUT IN AT ONCE! GOLLY! Good luck with your car!:)

Alternator or alternator pulley by any chance?

I have the same symptom. I had been thinking it was the clutch or flywheel, it sounded like loose bolts floating around. I finally got a new clutch and flywheel installed about 6 weeks ago, throwout bearing replaced too of course, but the sound is still there.

Last week on a hunch, I checked the idle voltage with a multimeter. It was fluctuating in the low to mid 13's and the fluctuations seemed to coincide with the rattle. Above 1,500 rpm's or so the rattle goes away and the voltage stays dead flat.

Is this enough evidence to buy a new alternator? Also, the voltage reading at a 3,000 rpm's was 13.9 and low 13's at idle. Is this normal or a little on the low side? I have an under-drive pulley installed. Below is a link to an alternator I have short-listed. Thoughts??

New Porsche 911 Boxster s H6 Alternator 120A 97 04 M T | eBay

Is your idle speed fluctuating, causing the Voltage changes?

JFP:

Could be possible to replace the input shaft bearing by removing the transmission case but leaving the gearbox installed..?

In some gearboxes, the casing for the input shaft bearing is cast inside the transmission housing.

.

Deja-Vu..?
 

JFP, somehow I may have asked this question previously, if so please ignore..

And they say "that stuff is not bad for you"

...sure LOL

.

Exactly. If you do have a single-mass flywheel, that could do it as well.

Don't want to hijack the thread but my 02S is at the transmission shop with the exact same issue.

I bought the parts. Clutch,Pressure Plate,Throw out Bearing, Flywheel, Transmission parts for 2nd gear issue.

Did anyone come out with a fix? I am wondering if the throw out bearing was bad out fo the box.


Thanks
Thom

It's the throw out bearing. You should have heard the one in my former E30 325is(with a new clutch)-it sounded like it had rocks in there with the clutch out.

Thom, do you mean the infamous bearings for the 6 speed (also on the 996)and the worn tooth problem for 2nd gear pop-out? If so this is an increasingly common problem with higher miles .It would be very useful to us if you could share details. If you are just using a detent or shift arrestor, I hope you took our advice and chose the best part?

Numbersix - I bought a Sach kit with the throw out bearing. Think it is bad out of the box?

Gelbster - My second gear would pop out and grind going into 2nd gear. Once they tore the transmission apart here are the parts they had me get.


999-917-546-00
Transmission Oil Man

996-302-942-00
Idler Gear 2ND

986-303-010-00
As Gearshift Rod

996-303-301-00
Spiral Clamping Pin

996-304-061-03
As Guiding Sleeve

996-304-611-00
Synchronizer Ring

996-304-613-20
Cone Ring

950-304-617-20
Synchronizer Ring

996-301-805-00
Shaft Sealing Ring

Wow ,that is an expensive shopping list[ I hope they are experts in this 6 speed 7/or the similar Audi 'box ? This is a very difficult unit to work on for the first time. Suggest you Search here nd in 996 Forums for Gearbox repair/rebuild. It is a task very few shops are qualified to tackle. A few of us have tried with some success but the task was very exacting for even experienced diy mechanics with deep pockets.
QUOTE=no1tmorrow;533248]Numbersix - I bought a Sach kit with the throw out bearing. Think it is bad out of the box?

Gelbster - My second gear would pop out and grind going into 2nd gear. Once they tore the transmission apart here are the parts they had me get.


999-917-546-00
Transmission Oil Man

996-302-942-00
Idler Gear 2ND

986-303-010-00
As Gearshift Rod

996-303-301-00
Spiral Clamping Pin

996-304-061-03
As Guiding Sleeve

996-304-611-00
Synchronizer Ring

996-304-613-20
Cone Ring

950-304-617-20
Synchronizer Ring

996-301-805-00
Shaft Sealing Ring[/QUOTE]

The throw out bearing is a new Sach bearing. I guess it could be bad out of the box. Do you all know there is anyway to test the bearing?

Thanks

I bought all the parts from sun set porsche parts for 1650.00ish(shipping is a little much)

If you like free shipping , try RND Euro Parts. Good prices too.