Deckard350z

Hello! Have had my 2007 Z with 39K for a few months - all good so far. (apart from an initial sensor thing) Now I'm noticing a throbbing kind of wobble - resulting directly from engine revs - through the accelerator pedal and even my seat - when the car is cold. Last night it stalled and wasn't happy. The power can be uneven and sporadic as well. As soon as it's warm...all good again. (I also think my fuel consumption is seriously bad) Bit of research suggest its injectors or plugs. My plan is to change all those out - and get an oil and filter change which is due. Am I on the right track here? Any informed thoughts appreciated. Cheers Matt