How can I fix a check engine light (CEL) in a pre-modified honda prelude?

so i bought this car a year ago and found that the check engine light wont go away no matter what i replace or fix. it comes and goes, but its always the same codes, P0172, P0170, both are for "Fuel trim bank one".....or atleast thats what comes up for Autozone OBD-II readback. I bought the car with mods already done to it....DC headers, Cold air intake, short-shift......