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.
There are two problems I have worked on relative to contaminated fuel.
In one case a nearly new car developed a huge amount of carbon build up on the top of the pistons. There are additives used in normal retail gasoline to prevent that. In this case the vehicle test guys weren't using retail gasoline from a known source. This carbon buildup occurred surprisingly quickly. If memory serves just at 1000 or 2000 miles on the odometer.
In the other case some contaminated gasoline (from a retail supplier) left deposits on the Heated Exhaust Gas Oxygen (HEGO) sensor degrading that device's performance. In my case the bad fuel actually set a diagnostic code. This happened within 30 minutes of filling the tank with suspect fuel.
Either of these issues would definitely have an adverse effect on horsepower performance.