I have had a few of these doing exactly the same issue , ok until it comes onto boost and pulling hard , the trouble is the fuel pressure sensor code is a bit of a red herring , the problem can be the fuel pressure control valve , it is being told to move and it is telling the PCm that it has moved but it is not controlling the fuel pressure correctly , sometimes due to swarf within the system . the best way is get a data logger test done see what the required pressure is and the actuall pressure , if they do not match chances are it is a IMV ( inlet metering valve ) that is sticking , it is getting the signal to move , it sends back the signal that it has moved but it has not altered , the bad news is that depending on what pump you have depends if you need just the IMV or a complete pump .