engine rattle

[melvin]

Just recently I have noticed a slight rattle when I give the car a slight rev while stationary, the rattle appears as the rev is coming down and then disappears at idle. It only seems to do it with the clutch out, if I hold the clutch in its ok. Any ideas what this could be?

Its a CDTi 150, 80k.

[mozzer99]

This is the Dual Mass Flywheel (DMF) with excessive clearance.
80k is exactly the mileage this seems to start on a 150bhp CDTI. Seems the power of this model is a bit too much for the DMF.
The old vectra 'B' 100 bhp diesel never has anything like the same amount of problems, nor does the 120 bhp Vectra 'C' version.
It can go on like this for a very long time without harm, however if you study the posts for 'DMF' you will see that rarely it can fail and damage the gearbox or just seize when it needs cutting off.

As it is very big and heavy job (six speed box is very heavy) to replace it is usual to replace the clutch , release bearing and flywheel bolts at the same time.
Parts are normally around £400. Main dealer inclusive is £1k. We have seen (rare) quotes on here for £500 fitted.

Link below shows a very similar DMF so you get the idea. 20mm movement is normal - this is plainly excessive.

http://www.youtube.com/watch?v=bFnLMQNKKH8