Originally Posted by black_jack

Agreed - (split boost hoses)

Also check EGR valve (bung a blanking plate on it, solid, stainless steel - fiver online)

And if its a variable vane turbo check its working properly (variable vanes can coke up & sieze and can have a knock-on effect on the actuator etc )

Worth sticking a code reader on it - if you don't have one (f- super is about £20 online)