Starting problems

Hello ive got a fiat ducato 2.0 jtd on a 04 year this van is becoming very frustrating with different aswers off so called mercanics fuel cutting out problem had new high pressure fuel pump new fuel presssure switch mass airflw changed still no luck wen you start the van it starts perfect no problems hot or cold wen you run the van it runs ok wen you dont throttle it as soon as you give it a bit of throttle it cuts out with the engine management engine light on or sometimes gos in to limp mode as soon as you turn the van off and then restart it it runs rite again until you throttle it again as anybody and the same problem as me with the same van it wud be very much appreiated if any body as got the answer to this problem on the fault codes all its coming up with is a fuel fault but how can it be wen the main fuel parts have been changed thanks clint