I posted a thread some time ago ref the blow-on-bottle-top noise due, I believe, to the wastegate sticking slightly open (Std UK 4-Dr 97MY).

Since owning the car (approx 10weeks) the noise seams to have gone away - only the other day, gently accelerating from about 2300 onwards it was there again. Does anyone know if this can be a self curing / forming problem?

Secondly I`ve also noticed a (very) slight hesitation / jerkiness when accelerating in 5th from about 2500rpm, seams to clear by around 3500-4000rpm. Could this be the ignition units starting to go off (as in the other `jerky` threads) or could this be associated with the wastegate issue?

Should there be absolutley NO humming-whistlely noise when accelerating or will you always get some due to solenoid cycling open/closed???????

All of the symptoms you describe belong to the Blow off valve problem, take the car to your dealer and they will replace it under warranty. The noise does come and go, but will stay longer and longer, the more you leave it.

You should get a high pitched whistle when the turbo spins up, and thats usually it, other than road noise and wind noise of course http://bbs.sidc.co.uk/smile.gif .

This should get in onto the daily forum....