fiat scudo 2.0jtd

can anybody help been repairing a scudo came to me with engine light on after putting on diagnostic came up with over boost valve.checked turbo waste gate,freed off egr valve checked exhaust for blockage,fitted new boost valve,vehicle goes ok when code is cleared till you travel at 70 then code comes back and vehicle lacks power again.basically great up to 70'

Cheers ian

hi, I've got exactly the same fault on a 2.0 jtd. Did you ever sort the fault out. Did your van also chug a bit then whap out a big puff of black smoke and stall???? I'm goin to try the mass air flow sensor in the next week or so. Could you let me know if you found it to be anything different , and if I sort it out I'l also repost and let you know what I have found