just went to smog...and HC (hydrocarbon) is a lil high off by couple digits... failed twice.....what can i do to lower the numbers ? is it that my cat needs to be replace or timing...or fuel ? help me out.........got ticket for modified intake now have to go to state ref...lots of HC (hydrocarbon)

i failed twice at state ref..........stock single cam d16z6
if your in northern kali bay area leave a # jdm_geo_metro_209@yahoo.com