This isn't a new problem, I've just noticed its not coming from where I thought it was originally. I was going over my engine bay today looking for PCV hoses that I have yet to fit and I thought id have a listen for the noise.

 

Basically its a shrill noise at 1.5k and at 2.5k coming from the drivers side of the engine, its been there for 18months and I have no smoke on that side. My left bank smokes at Idle but we have pretty much narrowed it down to PCV hoses (thanks to duffer and smw1).

 

Could it be a dodgy injector? after about 2 miles and once the engine is warmed up the noise dissapears and only reapears the follwing day when left toit over night. I only notice it because when cold my car idles at 1.5k revs for a few minutes until its up to tempreture, after that it revs at 750rpm (ive replaced offending sensors to stop it idling high)

I had the same sort of thing mate,

 

May sound strange but check your sump tank for dents. If it is dented then it will create a vaccum which could make this noice.

 

I'm having mine bashed out at the moment since the engines off, and I've been told that my stock turbo's are in very good condition as well :eek:

stupidly i posted this in the wrong forum,