Hi, had a slight misfire on my BMW, felt like a fuel problem that has got worse, it now had a blank spot when accelerating from 500-1000rpm seems okay over this with no back fire, I have replaced all filters plugs, leads, dist, ECU, cam sensor, and injectors and have checked the fuel pump, it now has no power under pressure, okish on the flat and down hill but struggles up hill, i have noticed that 1 and 4 plugs run dry and 2 and 3 are wet/normal could the 02 sensor and cat converter be the problem? I have no check engine code light on this model, Thanks