Thanks for the swift reply. I did a bit of digging on the part that you replaced and it looks like that isn't compatible with my motor. Instead my turbo has a vacuum type pressure valve which looks to be a fairly easy (and cheap) fix. I'm going to give this a try before going to the specialist. With a bit of luck, this will solve it. It's either between this or the pressure sensor, again, a cheap part to buy so I've ordered both. Let's see how it goes.