Hi I have a 2002 a3 1.9 tdi pd130 , I have an intermittent problem with the turbo power , most days it runs perfectly fine but every now and then the turbo power will play up ,sometimes ill get no power at all and end up struggling to do much more than 50mph( tried turning car on and off at this point no different) when it does this ill normally downshift through the gears and sometimes ill get a short burst of full turbo power , other times it might give me anything between 10-80% of the power it ahould do but that power can change alot over a journey I.e 20% from 1800-2200 rpm 90% 2200-2400 then 20% 2400 onwards ,as I say its intermittent it has been fine for a month but started doing it again just , ive cleaned out the egr valve , ran a couple bottlea of injector cleaner through ,any help appreciated