Style chooser

Hi i am currently driving a wira 1.5 mmc, the car CEL somtimes lit and off for quite long already and i beh tahan dy. i got two workshop men, they both telling me is o2 sensor problem. so i would like to ask how much is the price for half cut and new one genuine ( i think i won't go for the new one LOL). i want to chg it because i heard ppl said tht faulty o2sensor,fc higher. i don't know is right or wrong. :wavey: