2001 xsara picasso 2.0 HDi Boost pressure switch

[oscar]

Hi Had AA out as have a problem with fuel economy didnt seem to matter if doing 55 or 80 got similar instant economy and noticed range was going down anyway what else happened was had just under half tank 200 odd range had to stop on a steep hill just missed the handbrake/clutch bite point pulling away and stalled it. now 80 mile range and tank down to one bar? thought would come back once on flat but no stayed like it then when got to where staying revved it up and got cloud of black smoke each time.

AA got bosch machine out went through it all reset did runs few times as quite a few faults showing inc mass air flow meter anyway that was ok once reset along with other things but said the boost pressure switch is showing wrong but said can't get to it as round back to play more with it.

Is it it's own thing or controlled by an electrical solenoid switch?

[Hell Razor5543]

I wonder if it has the same arrangement as a Xantia 2.0L 110HP HDi engine? I believer there are two valves that are pressure controlled. On the Xantia I think (but I do NOT know) they are up high in the engine bay, mounted on the bulkhead on the left hand side (looking from the front of the car into the engine bay). I do not know where they are on a Picasso.