Problem with acceleration

[Lordblood]

I'm having a new issue now when accelerating. I'll put it in 5th gear at 35 MPH to cruise, but accelerating to 45 MPH the rev's will go as high as 5000 RPM as if I was in a lower gear, but then go back down to its proper less than 2000 RPM.

I'm thinking this is my clutch on its last legs slipping, but I have no idea to be honest. Any idea what this might be?

[Topless]

Yup. Clutch it is.

[Lordblood]

Originally Posted by Topless

Yup. Clutch it is.

So I have to change the clutch, any other things that needs repairs while I'm at it? Should I change the flywheel or leave it as it is?

[fragdude]

I believe your mechanic will take care of the things associated with changing a clutch such as a new throw out bearing, most likely resurfacing the fly wheel, new pressure plate if needed, etc. But you shouldn't need a new fly wheel. The clutches usually come in a kit with everything you need and the parts should not be more than 400 bucks. If your pressure plate is fine you only need to change the clutch and throw out bearing which lowers cost by a nice amount

http://www.pelicanparts.com/catalog/shopcart/996M/POR_996M_Tclutc_pg1.htm

Personally, if I was going that far into the engine I'd change the flywheel, Bentley says to scuff it with scotch bright if it's glazed; I don't like that idea at all.

[Kirk]

Yup, sounds like a slipping clutch. How many miles do you have on the current clutch? The link to Pelican Parts is good. You can get the pressure plate, clutch, and throw out bearing as a kit for about $400. You can simply check the flywheel to see if it's within the serviceable limit, which it probably is. There's no issue really with keeping it as long as it's clean. If not and there's enough material left, get it resurfaced. The replacement for my S at Pelican is $670. It can't hurt to change it, but if it's good, then why throw the money away?

Kirk

[Lordblood]

Thank you everyone, all of the posts have been very helpful!

Here's some more information about the issue: I am NOT working on it myself, way too much work to be doing, especially when I'm nearing finals week at school. So I'm getting an independent shop that does work on all European luxury brands (BMW, Merc, Porsche, etc.). I have no idea if this mechanic is experienced with Boxster RMS leaks, perhaps I can get another shop that does work on only Porsches and Ferrari's to look at it? (they charge a whole lot more, a flat rate of 90 bucks an hour for labor I hear).

I've had this car for 5 months now, and the previous owner said this was the original clutch, which means it now has around 92k miles on it. I haven't done a 90k service yet, so I guess this is a good opportunity to get that done as well. The big problem I'm having is that we need that Porsche as a daily driver, otherwise 2 people will be missing school/work. So we need to work that out, maybe a rental car is needed.

EDIT: oops, almost forgot, there IS a slight seepage from the RMS, just wanted to point that out.

[Cloudsurfer]

The light flywheel totally transformed the car. It gets rid of the typical German sluggish rev response and makes the motor MUCH more rev happy. Heel-toe downshifts are a breeze after the change. I swapped the flywheel on my last M3 too, and it, too, made a world of difference.

As to the noise, if you swap out the factory dual mass flywheel for a lightweight (which will be single mass), you should use a sprung centered clutch disc to allow for some damping in the system. This will eliminate most of the chatter.

If you are getting seepage, then you're likely going to need the RMS seal. If you're on the original clutch/ flywheel, I would almost certainly replace it after that many miles. Call it cheap insurance and a job done right. If you're not doing the job yourself, you're not going to want to pay the shop to pull the transaxle again after swapping just the clutch. While in there you might also think about updating the IMS seal (not the IMS itself) and using the new encapsulated bolts.

As to updating the IMS, unfortunately this requires splitting the cases of the engine, so it's only something that can be done at rebuild time.