I have been reading the 'threads' (or whatever) about the possible causes of the power going 'flat' with my 156 2.4 jtd when overtaking or when asking the engine to work hard and at mid range (2800 - 3000 rpm) just when changing up a gear. This coincides with the 'motor control system failure', 'go to dealer' icon appearing on the display screen. When connected to a snap-on computer it showed up two codes; EGR valve, and Boost Pressure. Initially I removed and cleaned the EGR valve but that made no difference. I then bit the bullet and bought and replaced the EGR valve but still the 'motor control system failure' showed on screen. Reconnection to the computer still showed two codes until we zeroed the codes, blasted the car up the road until it again showed the dreaded warning and then reconnected to the computer. Only one code showed up -- boost pressure. So now that the EGR fault has been eliminated, I have to turn my attention to the possible causes of high or low boost pressure. Having read some of the posted comments on this forum, I am realising that the variable vanes within the turbo might be stuck. But before I (or the garage) go wading into the turbo my questions are these - would the boost pressure have damaged the EGR valve or vice versa, would these two faults have in anyway damaged the ECU and does anyone out there have any further points of view on this problem? I apologise if this problem is one that has been discussed at length previously, but any Alfa owner who is suffering with this fault knows how frustrating and dangerous it can be, so all help will be appreciated. Thanks in advance.