Vectra problems?

Further to a recent question posted regarding starting problems on my 52 2.2 vectra sri dti. Having exhausted all other avenues, leak off pipes(renewed), injectors, glow plugs checked etc i am now told it must be the temp sensor within the fuel pump. My bill up to now is £200 and a fuel pump is £400 circa 2nd hand???
Can anyone confirm this is a common problem and probably the cause? . . . its giving me a serious headache is this car!!!!