if it is the pump its not too said a job to do, but the tank does have to be dropped at least. not always necessary to completely remove it as ive done a few pumps on normal foci, one thing to consider though is im unsure if the pumps in a shopping spec focus are the same as st170. the st uses a different fuel line setup without a return so i dunno if the pressures are different. BRAINWAVE>>>> PRESSURE REGULATOR ANYONE????????