Hi mate, sorry I probably could have made that clearer, the solenoid is ok, it was the vanes that were sticking.

So, we spent the day taking the turbo out, stripping it and found that the ring that moves the vanes was stuck rock solid, a huge amount of carbon and rusty stuff had built up and clogged it.

We cleaned it out with egr cleaner and now it's very clean and moves perfectly, so we're now putting it all back together and hoping for the best