We have a 2008 BMW 120D, which has developed a 'fuel surge'. Basically, in the last couple of months we have had to have a new DMF and Clutch fitted, a new fuel filter, then a few weeks later, the turbo went - an expense we could have done without. Anyway, when we had the turbo replaced the garage also did the following : new oil and filter(he flushed the engine through, and then fitted brand new filter), new air filter. On the diagnostics it came up with the following : Boost pressure actuator - Faulty, Air Mass Sensor - Faulty, and Exhaust gas recirculation rate - Internal fault. The garage said that as this was all related it was the turbo. Since the turbo has been done, the car has been fine. He checked the codes again after, and no codes flagged up. He has advised on the invoice that there is a possible fuel fault - vehicle surging. The car has been driving fine, but recently, when the fuel goes below quarter of a tank, the EML sometimes comes on. The car surges around 1500 to 2000 rpm. I have attached a copy of the graph he gave us, which he said the normal level should be around 300. Does anybody have an idea of what it could be?

Car diagnostic graph.jpg