Guys,

I've got a 99 UK Impreza with a PPP. It's done 105k miles. On a recent trackday it performed fine - but when I stopped for lunch to fill up for fuel, I noticed that on tick over and up to about 1,500 rpm there was a scratching noise (quite loud) from the turbo. When I loaded the Turbo and drove hard the rest of the day - it was fine, unless I left it ticking over.

On a day to day basis it is also fine - no noise at all all - it's like it's realted to the temp on the turbo. The turbo has to be HOT and being used for a long period of time (minutes at full throttle, rather than seconds) - which you only really get on a track day.

Any ideas? and can I change the parts rather than going for a full new turbo if that's the issue?

Cheers

James