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Hey all, I have an NA6 long nose with 250k+km that I weekend drive.
Just recently I have noticed some harsh vibrations coming through the gear lever and dash. (Gear knob is rattling off)
Seems to be engine speed dependant.
The first buzz is around 2.5 -3, and again from 4-4.5

Engine and ignition seems to be running fine otherwise.

Likely causes?
Harmonic balancer, engine mounts?
Thoughts

Cheers
Howard


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Could try parking the car, lifting the bonnet, giving the engine a good rev and see whatsa shaking under the bonnet.

Both motor mounts and the harmonic balancer are likely to be getting on if still original. They're both made with rubber that degrades.

You could give the engine a shove side to side to see if there's play. Also the harmonic balancer by hand, but when it degrades slipped timing is usually the issue.

Mechdude wrote:have an NA6 long nose
noticed some harsh vibrations coming through the gear lever and dash. (Gear knob is rattling off)
first buzz is around 2.5 -3, and again from 4-4.5

Exhaust manifold heat sheild & the other exhaust heat sheilds are all prone to buzzing & rattling during certain rev ranges when their mounts or tabs break, but not usually to the extent of rattling the gear knob off.
There's also a dash mounting point under the pside of the dash that eventually gives way that causes vibration.
Whilst rare, the long nose 1.6 & 1.8 have been know to suffer from much the same issue as the short nose 1.6.