hi all I bought a 2005 55reg focus st3 last week, and within a day the engine management light came on, I hade a diagnostics done 2 faults came up, first code was p0087, I think the second code he give was wrong, it was p2718, think it was ment to be p2178, he cleared the codes but light came back on nearly stairght away, I also think it went into limp mode as the was very little boost, I took the kam fuse out for half hour and the light went out and was boosting ok, drove 10 miles today light came back on, my m8 diagnose it again tonite and 1 fault code come up p0087 the car also felt lumpy today when idling, has any1 any advice what to change or check first?, fuel filter if it has 1 ? Petrol pump/relay? Pressure pump sensor ?, I'm totally skink after buying it and don't want to change any parts that don't need changing, if any 1 has any advice what to do or try first I'd really apreatate it, thanks in advanced.