Hi, firstly...when the car is stationary and ticking over the cabin vibrates quite a bit, throught the floor and sears, what are the signs of dmf failure?  Secondly...I have observed that the tensioner on the alternator belt seems to move a mm or so either way when pressured by hand and there is visible movement in the tensioner when the engines running alongside some faint squeezing - would this contribute to vibration as above ?? ( I have a berlingo with the same engine - slightly less powered, the tensioner on this looks identical and os solid).

Any input appreciated 

Thanks!

Just now, 757-200 said:

Hi, firstly...when the car is stationary and ticking over the cabin vibrates quite a bit, throught the floor and sears, what are the signs of dmf failure?  Secondly...I have observed that the tensioner on the alternator belt seems to move a mm or so either way when pressured by hand and there is visible movement in the tensioner when the engines running alongside some faint squeezing - would this contribute to vibration as above ?? ( I have a berlingo with the same engine - slightly less powered, the tensioner on this looks identical and os solid).

Any input appreciated 

Thanks!

I should have also mentioned that the car has had a new lower engine mount which I believe to be a common failure, this was replaced with an uprated version - could this be a consequence? 

 

Cheers

Anyone ?

The sprung tensioner is designed to move.  The solid one on your other car is probably seized up.  If it's a very large amount of movement then the alternator pulley clutch may be worn out.

I had the same issue on a Mk3 Focus with this engine.  Vibrations through the cabin.  I also tried the lower engine mount but no difference.  In the end I went back to VW for the comfort and refinement.

DMF's usually cause a heavy rattle at idle or under load, not just just a light vibration.