advice on boost issue needed

[knackaz]

as engine starts increasing boost, say past 4psi, the car starts to surge and go all on/off labouring. doesnt stall and doesnt make a difference whether in overdrive or normal drive (auto), apart from that the car runs sweet on cruising, but hit a slight ascent from 110km/h the boost starts to rise to compensate for engine load due to hill and it starts labouring. is this possibly the fuel pump problem not being able to deliver right amount of fuel?

dont believe it to be a air leak at this stage anywhere, but anythings possible,

so anyone with any more ideas apart from the rewiring of the fuel pum or a new fuel filter (which im doing this afternoon), im more than open to advice

thanks

[Nizmo]

i say its your fuel pump ..... mine did same at driver training under heavy acceleration it would surge n almost cut out ..... i have a Bosch 044 .... apparently they dont register the last 1/4 of the tank ...... maybe chuck it on the dyno and see. Once mine had a full belly of fuel she was fine - its just when you get down to the last 1/4.