alright folks im having some issues with my series 2 ,its as if its running on 3 cylinders just fitted a new cam and stage 2 head from specialised engines bought the car as a non runner its never went right im 100% sure the engine is fine so im thinking the mfi is playing up if i unplug the pressure rgulator it runs the same as if it was plugged in does anyone know what this means ,also fitted new injectors has anyone had a similar problem any advice would be greatly appreciated im close to putting a match to b$stard

 

has it got compression on the cylinder that missfires?