Porsche Enthusiasts Club Forum

I don't normally post over here in the dark side section but I wonder if you can point a new Porsche owner I've met in the right direction on an issue he has with a newly acquired C2. I'll just paste his question here from what he sent on another forum and maybe we can encourage him to come join us instead

Well after driving a problem free supercharged m3 e46 vert for 18 months i decided to sell her and move on to a porsche,so i went out there with a big pocket of cash looking at cars,i searched here and looked there finally i found one that ticked all the boxes,the right colour very nice interior turbo alloys,sports exhaust etc and although a little bit against what i wanted its got the 3.4 engine was hoping for the 3.6 c4 but got a 2000 porsche 996 3.4 sport vert with hard top...

had the car a week and things are not going well at all this week ive had 2 new back tyres,drivers side coffin arms and anti roll bar bushes at a cost of a grand fitted,"" gulp ""

but it hasnt fixed the reason im asking this on here my problem is that when i take my foot of the accelerator i get a vibration through the car that rattles the fillings loose in my teeth,ive had it on the ramp looking for problems such as exhaust rub, ive checked all the arms the wheels,im beggining to think of putting a for sale sign in the window, and going out and buying a m3 vert again as i had no issues with the m3, but had the total opposite from whats supposed to be a great car, to be honest at the moment i wouldnt tell anyone to think about buying a porsche..the parts are ridiculous so you cant say ill try this and try that, because every part on the running gear cost mega quids,has anyone any idea what can cause this is dosnt do it when im accelerating, just when i take my foot of the peddle and the car slows down to about 3000 revs and then makes the horrible vibration...



Any help would be appreciated and I can forward it on

Cheers

Andy

Some extra info Craig has sent me

exhaust bolts snapped i extracted the snaped ones and replaced with nice new ones makeing the car sound like a porsche should

then i checked the arms and rubbers had perished and come loose so replaced these,had 4 wheel laser alignment which was hugely out before...

the blower didnt work so i took the cover off and found a twig had got in and jammed the barrel blades stopping them from turning easy fix,

the car felt like it was on ice so i changed the anti roll bushes.

ive looked everywhere for this annoying vibration ,the best way i can explain it is the engine seems to be unbalanced like back in the day of the 40's and 45's ,when they had to be set right or it would be terrible, i would put it down to worn cams or maybe slight buckle in the crank but the engine is perfect, the power is awsome its just when i let off and let it ride down the gear, as soon as they are at 3000 revs its vibrating bad then when the revs get to about 2500 and it stops




Cheers guys I know we'll be able to help

Andy

Another question. Where did you buy it from & did you have a full mechanical independent inspection before you got it? Did you have the problem before fitting new tyres & did you have them on car balanced. If anything on the running drive shafts/wheels is out then an on car balance will correct that. Maybe it should be going back to where you got it.

J.J. I think Craig here needs to take it to a specialist. He says he's in Blackpool North West of Preston so advice on an indy in this area as Jon M is a little far for him to go

Thats Hartech country. Probably the best option. I fear there may be previous accident damage or a bad repair. Something out of balance for sure. http://www.hartech.org/

Is it rev' related or speed? Does it make the same vibration coming down from 3000 to 2000 in all gears? Or is it at a certain speed?

....when i take my foot of the accelerator i get a vibration through the car that rattles the fillings loose in my teeth,ive had it on the ramp looking for problems such as exhaust rub, ive checked all the arms the wheels.....
....the power is awsome its just when i let off and let it ride down the gear, as soon as they are at 3000 revs its vibrating bad then when the revs get to about 2500 and it stops....
Thats all the info he's given me so far. I'll pass on Hartech info to him. This go between lark is getting tiring

Why is it only front engined water-cooled guys trying to help, have you pi**ed off the people from this side of the forum Andy?

Lee

More info,
the tyres are balanced ive just had the camber and alignment done,as soon as the revs hit 2000 not 3000 it vibrates no matter what gear its in although its tiptronic lol.
ive ordered engine mounts today so hoping that cures it.if not im taking the engine out and sending it off to be balanced to see if thats the problem


I'm getting Craig to log on here himself and he can sort the rest out so be nice

Sounds like its time to take it to a proper specialist, like Harteck, they will probably diagnose the problem in no time, do not believe that coming at the problem from several directions at once will serve you well, If this is a standard unmodified engine I would be massively surprised if it needed balancing,plus its a boxer motor, the squarest engine configuration there is, take it to a specialist