ST170 Fuel system

[TrentST]

Hey guys and girls.

Issue: My car is running very badly :togo:

The problem is revs and I can't, after 3500rpm, get any on board before the car starts to spluter around and go through stages of stalling. It finally died yesterday so I put it on a towtruck and sent it to the mechanic (repco repairer) where upon inspection with a diag computer insisted the problem was fixed (the engine light was off when I got into the car and started).

As I was driving home it came back.... I just want to know if there is anything I should be focusing on to fix this problem...

Cheers. :/