Interesting. Mine was quite apparent - but misleading.

I asked this question before on Porsche Pete's board which is now defunct. and can't find any archines.

I am looking for feed back from other boxsters' that use his technomount. Is there more vibration at 3000rpm?

My engine vibrates when coming off the gas at around 3000rpm... just wondering if this is normal with the technomount.... This is the only thing that bothers me on it... Wondering if I should look at the transmission mounts too...

Peter

I want to know too about this issue too. I get buzzing / rattling coming off the throttle or running at neutral throttle 2,800 - 3,000 RPM. More speifically at 2,800. 1999 car with only 35K miles. Im thinking the mount always discussed is right behind the removable fire wall behind the seats but the buzzing does not sound that close...? I dont seem to hear it coming "from behind the firewall" so much?

I have read the factory mount can cause a noise. Is that probably my problem? Guaranteed way to diagnose? I recall only hearing good things about Pedro's replacement but understand hard to get now.

Thoughts?

... it's inherent to the M96 engine.
The mount will dampen some of those vibrations if you have a new OEM mount installed.
The TechnoMount used (not offered anymore) more dense material hence more vibrations were transmitted.
Both, the TechnoMount and the OEM are wear items and should be checked and/or replaced at about 40K mile intervals.
Because the TechnoMount isn't offered anymore I recommend installing the OEM mount from the 2008 Cayman S.
Part number: 987.375.023.03. Bert Smith Porsche offers it for $116.84: [bertsmithparts.com]
Happy Boxstering,
Pedro

Pedro Bonilla
1998 Boxster 986 - 311,000+ miles: [www.PedrosGarage.com]
PCA National Club Racing Scrutineer - PCA National HPDE Instructor - PCA Technical Committee (Boxster/Cayman)

---

Racecar spelled backwards is Racecar

"Racing is life. Anything before or after is just waiting" ... Steve McQueen as Michael Delaney in "LeMans"

"If you wait, all that happens is that you get older"... Mario Andretti

"Being second is to be the first of the ones who lose" ... Ayrton Senna

Predo

A very good import indi tech who knows performance cars told me the 2,800 - 3,000 RPM neutral throttle buzz was related to the vario cam. For some reason around that RPM the chain might have a brief moment of less tension and will produce noise. He commented that it seemd to be less apparent with the A/C on etc... Meaning whenver the engine has more load. It's loadest when at neutral throttle without A/C.... Meaning no load on engine... BUGS THE HELL OUT OF ME... Some drive I can't seem to make it happen. Sometimes its load...

I know some of the 8 cyl BMW cars in the late 90's had problems with chain tensioners etc and would eventualy allow the chain to run loose and the chain guides would break etc.... Worries here?

Feel free to tell me to search the forum in more detail if this has been talked to death by chance....

FYI, I did an oil analisys that came back very good with low metal readings... I do anual oil changes with Mobil 0-40. Next change will be 15-50.

Again 1999 base model with 35K miles. I do spirited weekend pleasure street driving.

... your low mileage, 15W50 may be a bit too viscous.
We generally recommend the 15W50 for warmer climates in the summer months or being tracked and/or for higher mileage cars where tolerances are a bit looser and would benefit from a heavier oil viscosity.
Happy Boxstering,
Pedro

Pedro Bonilla
1998 Boxster 986 - 311,000+ miles: [www.PedrosGarage.com]
PCA National Club Racing Scrutineer - PCA National HPDE Instructor - PCA Technical Committee (Boxster/Cayman)

---

Racecar spelled backwards is Racecar

"Racing is life. Anything before or after is just waiting" ... Steve McQueen as Michael Delaney in "LeMans"

"If you wait, all that happens is that you get older"... Mario Andretti

"Being second is to be the first of the ones who lose" ... Ayrton Senna

South Carolina.....

If you are feeling enough of the 3000 rpm vibration to be annoyed/bothered/concerned about it (as I was) - your motor mount may well be broken (mine was (2001 base).

I replaced it w/ the 2008 Cayman S. mount (Part number: 987.375.023.03) Pedro mentioned and the vibes were diminished to the point that unless you actively try to notice them you don't even feel them anymore.

Petee - That's exactly how my car felt - like you were driving over rumble strips. I likened it to driving over gravel.

Whether your current mount is broken or not, I'll bet if you replace it w/ the 2008 Cayman S. mount (Part number: 987.375.023.03) your car will be beautifully smooth, mine is.

BNSC - Same advice for you.

Just do it. It's not that difficult or expensive. You can thank me later.

I had that vibration before I replaced the motor mount and I still have it after.

What is it really then? The mount in question is right below the sep belt area just behind the seats, yes? My noise does not seem to come from there... Im thinking I would hear it from just behind the seats if it was the mount and it does not seem that way. Could it be the chain? I know some people do use aftermarket tensioners etc...
Is bad mount super easy to check...?
Im doing an oil change soon...

We're talking about a sympathetic resonance between the car and the engine when the engine is turning at ~3000 rpm. It happens with new cars and old cars. The newer style motor mounts somewhat ameliorate the problem.

To respond to your questions, a bad motor mount has more than one possible symptom. More difficult shifting, more vibration, and a clunking sound on hard acceleration are the most common. The clunking sound would come from the bottom part of the front of the engine.

To check a motor mount you have to remove it. It is not very difficult or time consuming to remove. The original motor mounts reliably wear out somewhere between 40-60k miles so mileage is a good indicator of need to replace.

1999 with 35K miles. I dont think my mount is bad... Probably other issues that apparently are not easy to fix. Maybe replace my mount in a few years or in amount 10,000 miles... At the 15 year mark I was going to make the rounds on a few items due to time etc...

Boxsterra - thanks for the reply. My Technomount was installed in 2009, with about 15K miles on it. As far as I can remember, the vibration I feel has been the same since installing the mount. Shifting has improved. I believe my old mount had the rubber ripped about 2/3'rd of the way around. It almost feels like i'm going over rumble strips at that rpm.



BNSC100 - rubber gets old. maybe it is aged.

Petee - That's exactly how my car felt - like you were driving over rumble strips. I likened it to driving over gravel.

Whether your current mount is broken or not, I'll bet if you replace it w/ the 2008 Cayman S. mount (Part number: 987.375.023.03) your car will be beautifully smooth, mine is.

BNSC - Same advice for you.

Just do it. It's not that difficult or expensive. You can thank me later.

Ok. Reasonablely easy DIY? I think Pedro has a procudure posted, yes?

NOTE: My car is smooth. No rough ride at that RPM. Just sounds like a pie pan rattling, but no vibration can I feel really at all.... Just the sound..... Wondering if the mount will change the sound...

Yes, Pedro has procedure posted here [pedrosgarage.com]

Not exactly easy, but doable.

HOWEVER - if you're not getting the vibes and it's only a noise/rattle, I don't think changing the mount will help. I'd be looking for loose/cracked/broken heat shields, exhaust or underbody plastic panels.

I think you are probably right... Had one person look at it and they said chain, but who knows..... ride is smooth..

Hi Pedro,

I think I asked you this before.... was wondering what you thought about users modifying their techno mount to lessen the vibration the felt by the driver.

My take is that the mount is too stiff.... I understand that you have concerns about the longevity of the mount if more holes are drilled, but I am thinking something along the lines of drilling 3/16" holes about 2/3's the way through the urethane that you put in. Offset the holes, so half are going in from the passenger side/ half from the driver side.

I may fill the holes with a softer compound such as a flexible silicon like GOOP. Maybe a Petee mod to Pedro's mount?

Been unemployed for the past 6 months, so I'm a little hesitant on laying down $150+ cash right now to get a new mount shipped to me in Canada.

Peter

If you take out too much material the core will fail.
The original TechnoMount was developed as a performance part that would allow an extra 3-4 HP to the rear wheels.
It was never intended as vibration-damping part.
As a matter of fact we advertised that it would pass more vibrations into the cabin.
Eventually, we stopped offering it.
Happy Boxstering,
Pedro

Pedro Bonilla
1998 Boxster 986 - 311,000+ miles: [www.PedrosGarage.com]
PCA National Club Racing Scrutineer - PCA National HPDE Instructor - PCA Technical Committee (Boxster/Cayman)

---

Racecar spelled backwards is Racecar

"Racing is life. Anything before or after is just waiting" ... Steve McQueen as Michael Delaney in "LeMans"

"If you wait, all that happens is that you get older"... Mario Andretti

"Being second is to be the first of the ones who lose" ... Ayrton Senna

its very durable, and it improves the shifting precision, which is especially nice under pressure on the track.

The bad news is that my NVH went WAY, WAY up, and its not just at 3k - it varies based on whether you are steady rpm, revs climbing, or falling. The worst for me is revs falling from about 3700 don to 3000. PITA on the highway. Nice on the track.

I have the enthusiast mount - the softer of the two.

Grant

Grant

gee-lenahan-at-gee-mail-dot-com

Years ago when I had the Boxster in for something else a tech found the front mount bad on my 02 Boxster.

I didn't have a clue it was bad. The tech though clearly showed me the cracked rubber and the inability of the thing to keep the engine from moving about.

Of course I had him replace it but even afterwards the mild vibration at 3K especially when coming from higher up coasting in gear under closed throttle was still present. In fact I can't recall noting any change in the car after the mount was replaced, though I like to think the shifter moved about a bit less.

Of course not being able to experience the symptom you report first-hand means what I have to say may be wrong, but I think the vibration you are feeling is normal.

The vibration as best I can find out does not come from the VarioCam system as it is not activated nor deactivated at the rpm range.

What is activated when reaching 3K and then deactivated when dipping below 3K is the resonance flap in the intake manifold.

And there is some harmonics of the engine, drivetrain, and suspension coupled with the road surface, tire conditon: wear, hardess, balance); all of which play a role.

I have felt this vibration at varying degrees of severity, in a few cases it has appeared at rather unexpected times enough to have me momentarily think something's amiss but the engine shows no other symptoms of any distress, there has never been a CEL, and the vibration is almost impossible to reproduce since the road surface plays a role and this varies sometimes quite a bit even over a distance of just a fraction of a mile.

But like I said above I'm not at your car and can't experience firsthand the symptoms. I would have to believe that if the camshaft chain tensioner were the cause there would be clearer indications of this. The DME keeps pretty close tabs on the camshafts adn their positions and if there was any discrepancy between what was reported and what was expected I think you'd see the CEL on.

Also if a cam chain tensioner was unable to maintain sufficient tension against the chain -- highly unlikely unless the engine suffered a severe loss of oil pressure or the tensioner was just bad (but it would be bad all the time and the CEL would be on) -- you'd spot pieces of the cam chain tensioner/guide rail material (composite plastic: there are two different colors: a dark caramel (almost black) color and a medium caramel color) in the oil filter housing oil and in the oil filter element. The improperly tensioned chain would be slapping against the composite plastic material and it can't withstand this long.

Sincerely,

MarcW.

It ave every indication of a (rear) wheel out of balance. At about 70 mph the car began a steady creep into vibrations.

I diagnosed it through a lucky flash of insight - and decided to downshift to 4th, then 3rd at 80 mph to see if the problem changed.

It went away. Ergo it could NOT be running gear - had to be motor vibration. It was the mount.

The replacement is so stiff it too causes similar vibrations. But the drive train re,mains in place. I suspect this differs by year and motor.

Grant

Grant

gee-lenahan-at-gee-mail-dot-com