vibration at 3200 rpm - 986 Forum - The Community for Porsche Boxster & Cayman Owners

golfchaos · 08-30-2004, 06:02 PM

I have a 2002 Boxster with 23,000 miles. It is a 5 speed. I have owned the car since May of 2004. The clutch was replaced at 20,000 miles. (prior owner rode it!) With the aforementioned as background, I recently picked up a vibration/deep rumble/noise?? It occurs between 3000 and 3200 rpms. It does not matter what gear I am in. I first noticed it coming down from a speed of 90 on the interstate. It has persisted for the last couple of months. I took it to the dealer today and the mechanic thinks it is due to the variable camshaft. He said he had seen it before and there was nothing to do. I just need to live with it. Unfortunately, I think he is wrong! It didn't do it for the first year that I owned the car, why should it do it now?! Anyone have any helpful thoughts or experiences?
Thanks

PeterJoyce · 08-30-2004, 06:06 PM

Take it to another dealer to get a seccond opinon.

Brad Roberts · 08-30-2004, 06:45 PM

I would like to dig a little deeper to understand when this is happening:

Are you off the gas with the car in gear (coasting down ?)

Can you feel it in your hands (IE the steering wheel)

Can you feel it in your backside (nice way of saying ASS ?)

What about with your hand on the shifter ?

There is an issue with the early 996 engines and failure of the variocam pieces.

B

charliemonoxide · 05-23-2005, 10:53 PM

I wish this problem wasn't happening to any of us, but I must admit that I am not the only one, and that somehow makes me feel better about it.

I purchased my 2000 Boxter in December 04 with 50k miles on it. I have since put another 7500 miles on the car. I noticed the vibration when I bought the car, but since I was getting a great deal on the sales price, and because I believed it to be a wheel balancing issue, it didn't bother me.

I must have been overly excited about buying this car because I did not stop to think that the vibration problem occurs not at a given speed, but rather at a given RPM!

Here are the details:

The vibration occurs at between 3000 and 3200 RPM.

It occurs in any gear (except reverse...I'm not crazy enough to try that!)

It occurs in neutral or coasting with the clutch depressed.

It does not matter what speed the car is traveling.

The vibration is not felt through the steering wheel nor the shifter, but it might be felt slightly through the seat.

The sound of the vibration seems to be more like a low rumbling buzz that seems to permeate the cockpit. It gives off the same sound one might expect when a wheel is out-of-balance, but there is no shimmy.

After I had the wheels high-speed balanced I realized it could be something much more serious, and for the first month I owned the car I was worried that I had bought a looser, but the problem has endured over 7500 miles and has not become any worse nor any better. I contemplated that it might be a motor mount problem, but I do not have any of the klunk noises when taking off rapidly, a problem that people on this web site have associated with motor mounts.

So, I am quite interested to learn what some of the potential solutions to the problem might be.

(aint' this web site GREAT!)

deliriousga · 06-24-2005, 07:01 PM

Mine vibrates in the same area. Only when the car is in gear and the clutch is out. It's smooth as silk until you hit the 3000-3200 rpm range on deceleration then you get the vibration.

I'm thinking it's a bearing problem in the clutch or drive shaft. I've never been in the clutch or drive system on the Boxster so I don't know if it has a "torque tube" like the 928 with more bearings. I'd imagine it doesn't since the engine is right on top of the transmission.

I'm going to pull the clutch some time in the next couple of months and see if any bearings have play in them. I'll probably go ahead and just replace the pilot and release bearings while it's open and check the RMS. I'll post what I find when I get around to actually doing it.

DevNull · 07-01-2005, 01:10 PM

My 2k2 did the same thing when I picked it up with 28k on the clock. I finally took it to the dealer to diagnose. Turns out the dual-mass flywheel was failing and parts of the clutch material had released (about a half inch ring all the way around one side).

Flywheel was replaced under warranty along with the RMS. Clutch parts ran about $600.

This definately fixed the problem in my case.

JoshMD · 11-26-2007, 09:55 AM

Hmmm I wonder if mine does this, I'll check after work.

That is interesting how adjusting the muffler height would get rid of engine vibrations. Who would have thought? (besides this guy)

PSL-Boxster · 02-01-2008, 06:30 PM

Quote:

Originally Posted by deliriousga

Mine vibrates in the same area. Only when the car is in gear and the clutch is out. It's smooth as silk until you hit the 3000-3200 rpm range on deceleration then you get the vibration.

I'm thinking it's a bearing problem in the clutch or drive shaft. I've never been in the clutch or drive system on the Boxster so I don't know if it has a "torque tube" like the 928 with more bearings. I'd imagine it doesn't since the engine is right on top of the transmission.

I'm going to pull the clutch some time in the next couple of months and see if any bearings have play in them. I'll probably go ahead and just replace the pilot and release bearings while it's open and check the RMS. I'll post what I find when I get around to actually doing it.

03 2.7 5spd 45k miles... i had same problem at about the same rpm, i got it checked at a dealer and it came up as a bad strut bearing. The estimated cost to fix was $800 , which is a total rip off.

JTP · 11-09-2010, 05:45 AM

I just recently got new tires and I've noticed the vibration on deceleration and some vibration at speeds above 80. The steering wheel shimmies a little at high speed cruising but not during the vibration during deceleration. That one is felt mostly through the seat. I initially thought the tires weren't balanced correctly so I had the shop double check and it was good. I also had a four wheel alignment done with tire purchase.
Seems like others have had this problem. I'm going to try checking the CVJ later today and see if they are bad. I had one side replaced 3 months ago so maybe the other side is going? I've also read this could be a bad DMFW, exhaust, or a failing Variocam?
I have a 2000 S 6spd.

The Radium King · 11-09-2010, 07:39 AM

there's a guy (spongebob?) who changed is flywheel and the problem stayed. from what i've read, the variocam issue is in the 2000 to 2200 rpm range so is a different beast. any successes i've heard of with the 3000 to 3200 vibration issue have been from exhaust changes; uncertain how a change in tires would interact with that, however.

JTP · 11-09-2010, 09:20 AM

What do you mean by exhaust changes? I have the original stock setup, entire car is totally stock. Does something change over time to the muffler?

spongebob · 11-09-2010, 10:46 AM

Quote:

Originally Posted by The Radium King

there's a guy (spongebob?) who changed is flywheel and the problem stayed. from what i've read, the variocam issue is in the 2000 to 2200 rpm range so is a different beast. any successes i've heard of with the 3000 to 3200 vibration issue have been from exhaust changes; uncertain how a change in tires would interact with that, however.

Correct Radium King,no change at all regarding vibrations wheen I changed my flywheel.
And as you say this problem is in someway connected with the exhaust because the vibration can be less noticeable after altering the tension between the u-pipes and the bracket in front of the exhaust. Maybe not the root cause though.
Wonder what Jake has to say about this? Is it just internal imbalance that causes this or some kind of resonance in the intake/exhaust system

clickman · 11-10-2010, 09:13 AM

If you do a search, you'll find some who say it might be the exhaust, some say it might be the clutch / flywheel, and others say it might be a worn front engine mount. Some have reported success with their repairs and others not.

I have the vibration too. I just live with it.

JTP · 11-10-2010, 10:32 AM

Quote:

Originally Posted by clickman

If you do a search, you'll find some who say it might be the exhaust, some say it might be the clutch / flywheel, and others say it might be a worn front engine mount. Some have reported success with their repairs and others not.

I have the vibration too. I just live with it.

So far my search has found nothing definitive. I did discover that one of my CV boots is ripped but no noticeable lateral play in the joint, but I'll start from there.

BerneseMtnDog · 11-10-2010, 12:35 PM

A failing front motor mount will cause a vibration at 3k. Mine did and a new mount fixed it. The older mounts could fail early due to a wimpy design and the newer mount has more rubber in it and is much stiffer. Hopefully it'll last longer. The old mount would make practically the whole cabin resonate.

Steve

2000 2.7L

yimmy149 · 11-11-2010, 01:07 PM

Even if it's not the front engine mount, you will notice other benefits by replacing it on an 8 year old car. I did mine a while back (on an 01) and it's a night and day difference.

-james

JTP · 11-11-2010, 01:30 PM

I did a quick check by seeing if the exhaust tips move on acceleration and the didn't move a significant amount. I'll get a better look actually looking at the mount. I may replace it anyway since it's 10 yrs old now.