Good morning everyone. I have a problem regarding the boost pressure on an Alfa Romeo Giulietta 1400 turbo Multiair 170 hp. [...]

Under full acceleration, the car starts to jerk and the boost pressure changes abruptly from 1.5 to 1 bar and vice versa.

The defect disappears if the engine is squeezed hard (for a few kilometres) and reappears as soon as the instrument panel is switched off and on again.

No errors are found in the diagnosis. Has anyone already experienced a similar fault?