99 transit diesel pick up 2.5 all cylinders working ok but have barely half the power , runs fine but embarassingly slow, can still use even with ton or more on, unless the hill's too steep, thinking it may be fuel pump, but would value any advice.
had two or three trannys like that,when they hit a hill they just died,no power,ended up sending the fuel pumps away to be overhauled,torx ring in pump breaks up,think that was the term they used,good luck
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