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My Mazda BT50, has been struggling to accelerate past 2000rpm on the gauge. So I remove and cleaned the fuel tank, and also changed the fuel filter but I am still having the same problem of engine not powering when at neutral, or even low gears has no power. Recently, when i pump the prima pump,the engine seems to pickup a bit but when I stopped pumping, it reduces. I can't figure out what was the problem. Is it the prima pump or the injector pump.Please assist.