944S2 mysterious noise
Discussion
When my car is warm, for a few moments when slowing down I get a vibration that I can feel through the pedals and a slight noise. The noise only happens below 2500 revs and is constant, not changing tone or pitch with engine revs. I have had all the belts done and the water pump checked as well as replacing the offside engine mounting. Could it be the nearside mounting? Has anyone any ideas?
I have ruled the balancer belt out as I have had it replaced, the noise is exactly the same after the change. The noise disapears after a short while, which it would not if it were the belt. The noise is not there when the car is cold or on the move, just when slowing down and stationary. I am puzzled.
What sort of noise is it? I've still got problems with a heatshield that vibrates as I pass 3000rpm, but in the past it only seemed to happen when slowing down and then it went away in the summer. Came back worse in the winter and had it sorted at the last service but it started vibrating again after a few days use. Can't feel it through the pedals though, so maybe unrelated.
pjs917 said:
I have ruled the balancer belt out as I have had it replaced, the noise is exactly the same after the change.
The balance shaft belt tension should be checked 1,800 miles after replacement, as the tension decreases much on a new one.
I checked mine after 2,000 miles and it would have slipped a tooth (or even worse) had I kept on driving.
I also have a heat-related vibration, but I believe it comes from the transmission/clutch ...
Jack up the car, get access to the bellhousing of the torque tube on the gear box side, disconnect the drive shaft from the primary gear box shaft and try to rotate the drive shaft.
When the rubber of the clutch is damaged, the drive shaft can then rotate 1/6 of a turn (60°).
The whole replacement procedure is here
>> Edited by Thom on Friday 27th February 14:29
When the rubber of the clutch is damaged, the drive shaft can then rotate 1/6 of a turn (60°).
The whole replacement procedure is here
>> Edited by Thom on Friday 27th February 14:29
Best thing to do is get someone to hold the car at a steady 2500 so the vibe starts and then get your head in, under and around everywhere until you pinpoint it.
One of my front brake shields vibrates at 2800 rpm because its slightly rusty and the nut doesn't hold it securely. Something to be changed when the disks wear out.
Also check the heat shield on your cat, these rust and can rattle.
Alternatively console yourself that the car has character
and enjoy the vibe (whilst blanking from your mind that pieces are starting to fall off 
)
One of my front brake shields vibrates at 2800 rpm because its slightly rusty and the nut doesn't hold it securely. Something to be changed when the disks wear out.
Also check the heat shield on your cat, these rust and can rattle.
Alternatively console yourself that the car has character
and enjoy the vibe (whilst blanking from your mind that pieces are starting to fall off )
It's possible the balance shaft belt was installed with the shafts 180-degrees off, or perhaps a bit more. Perhaps a hot belt doesn't sound the same as a cold one?
If you are experiencing vibration on a S2, I would think the balance shafts are the problem, as I purchased mine with the balance shaft belt broken and I did not know for sure, as it ran well and just had a slight hint of vibration at certain speeds. Better check into it now, as the balance belt can jump into the timing belt and cause major damage.
Dogsharks
If you are experiencing vibration on a S2, I would think the balance shafts are the problem, as I purchased mine with the balance shaft belt broken and I did not know for sure, as it ran well and just had a slight hint of vibration at certain speeds. Better check into it now, as the balance belt can jump into the timing belt and cause major damage.
Dogsharks
Thanks for all these but I know it is not the balancer shaft or belt. I have had a broken belt and a incorrectly fitted belt before and the vibration is not as servere. The noise is also more external, I think I am going to change the nearside engine as the noise/vibration is heat related.
pjs917 said:
Thanks for all these but I know it is not the balancer shaft or belt. I have had a broken belt and a incorrectly fitted belt before and the vibration is not as servere. The noise is also more external, I think I am going to change the nearside engine as the noise/vibration is heat related.
This is a long shot as this thread is very old, but did you ever find out what is was? I've the same and it's driving me mad. Take care, Andrew Gassing Station | Porsche General | Top of Page | What's New | My Stuff