Hi there, I am having an absolute nightmare with my 307. It's a 2.0 HDi sport 2005 reg. my engine management light is on and has the message "depollution system faulty" come up on the screen. It runs fine but the turbo doesn't always kick in. It's been in and out of the garage for the last 2-3 weeks or so. They have had a guy with specialist equipment come out and spent around 8 hours in total doing various tests on it. He narrowed the issue down to a solenoid at the back of the engine, so they changed it, took it for a test drive and 5 mins up the road the light comes back on and the turbo cuts out! They are at a bit of a brick wall with it. The light is always on but its hit and miss if the turbo works or not. They said something about there being a vacuum that goes round to the back of the engine going in and an out vacuum. There isn't always a vacuum coming out but they can't work out why as there are no leaks that they can find. Has anyone else had this problem or heard of anything similar? I've only had the car just over 2 months and I really don't want to have to get rid of it.