funny noise in Golf GT TDI

[bryan35]

Got a golf PD150 with 'apparently' the PD165 ECU upgrade and a tuning box for another 21% on top of that.

Anyway, I have noticed, and only occasionally, a nasty metal on metal/grating/not happy sound under certain conditions. It seems to happen when changing down and cornering as the clutch is released, infact lifting and pressing the clutch can make it come and go in these circumstances. Again, only happens now and again, and you can't 'make' it happen to repeat the fault.

also recently had occasions such as at traffic lights when 1st gear is a bit difficult.

any ideas?

[jeffc]

last time I heard a noise like that my bellhousing bolts had fell out on a fiesta xr2 and the flywheel was wizzing away at the alloy housing when you backd off the throttle !

dual mass flyheel is common but more of a knock than a grate noise ?