PASM

[Jimbo1271]

Hi all,
I have an 05 plate 997c2S 3.8 with the sports chrono option the car has 37000 on the clock and has not been driven hard by any stretch on the imagination, it is still on its original clutch, the front tyres are still the original ones from new and the rear tyres were changed for the first time about 3 months ago.
I'm really happy with the car and it drives amazingly well, I've had it for several months and bought it on 32000 miles. Shortly after bnuying the car I noticed a faint knocking sound from the front suspension, Its a muffled sound similar to the sound of a loose baffle in an exhaust box when you shake it. On smooth surfaces it's un-noticeable but at very slow speeds on a rough surface it is very noticeable.
Took my car in for a service (main dealer) about 3 months ago and pointed the noise out to the technician and he agreed there was a problem but in the time he had the car he couldn't identify it. Took my car back about a month ago booked it in for them to investigate the problem, did a second road test with a different technician and he again agreed there was a problem, they had the car for a week then told me it was fixed. On collection the car was exactly the same as it was when I had left it with them. Car was left with them a second time and again a week later collected the car only to find that the car was still exactly the same. They have the car now for a fourth time and now I'm being informed that the noise is normal for low mileage 911's with PASM... Can anyone out there confirm that standard PASM systems are "inherently noisy" I can't believe that top quality Bilsteins that were all the rage when they were introduced on the 911 are inherently noisy. Should these be covered under the Porsche warranty?
Any thoughts greatly appreciated..

 

[tscaptain]

On the 997 warranty survey (which sadly as a non-member you can't see!) there are very few issues with the suspension, mostly bushes and nothing on the PASM. I don't recall PASM being "inherently noisy". However, I am more amazed at the mileage from one set of tyres!! Are you certain they are the originals?

 

[mascanes]

You might want to try and find the thread that “berty987” wrote a few months ago under the Boxsters forum. He and I had problems with the PASM Dampers knocking on the rear of our Boxsters. Mine started knocking at very early mileage about 16k and never really got any worse up to 47k when I sold it. I lived with it because it actual got less noisy after it drove the car a few miles. I believe these dampers are the same front and rear and the same on the 911's. My OPC never found the problem, but I believe Mike (berty987) actually got one of his changed under warranty. You never know it might be something like this………. just a thought ........[8|]

 

[Jimbo1271]

Thanks for the reply I'll try and find that post by "berty987" Guess I'm going to have to try and live with it... It's one of my front dampers that are knocking and the rears are fine, I just hope it stays that way and doesn't get any worse. I checked the dates on the tyres and they were all 05's, front tyres are worn and rubber is a bit cracked now so need changing, don't know what kind of mileage is normal but I suppose 5 years does sound quite impressive...

 

[daro911]

ORIGINAL: Jimbo1271 Thanks for the reply I'll try and find that post by "berty987" Guess I'm going to have to try and live with it... It's one of my front dampers that are knocking and the rears are fine, I just hope it stays that way and doesn't get any worse. I checked the dates on the tyres and they were all 05's, front tyres are worn and rubber is a bit cracked now so need changing, don't know what kind of mileage is normal but I suppose 5 years does sound quite impressive...

Tyres might be dated 05 but could have been fitted at any time (old stock) PASM / Berty987 link below http://www.porscheclubgbforum.com/tm.asp?m=496597&mpage=1&key=&#496597

 

[dereksharpuk]

I have had 4 modern Porsches fitted with PASM. I have not had much problem with knocking, though over speed bumps when cold I found all my cars knocked. My main gripe about PASM in the Cab is the almost lack of change when selecting Sport mode. You get either firm with Normal selected or just a little firmer with Sport. On several occasion I wondered if the system was actually working!

 

[Rodney Naghar]

With all due respect, the OPC technician doesn't know what he's talking about. Knocking sounds from the suspension area are quite common and are almost always due to the usual suspects (not withstanding Berty987's damper issues which is quite rare) Go to an independent Porsche specialist in your area, and they will quite likely tell you that the culprit is either the:- 1.Anti-roll bar drop links 2.Anti-roll bar bushes delaminating 3.Forked control arm (coffin arm) bushes delaminating. 1 & 2 are very cheap fixes, 3 not as cheap but not unreasonably so. You do not have to live with this problem.