ive got a 2012 mustang gt with long tube headers and full exhaust trying to get to pass emissions. Catalyst monitor is setting and only code its throwing is system too lean bank 1 and same for bank 2. is it possible to go to engine diag>exhaust>rich/lean DTC and just change the thresholds to get the code to stop? anyone that's had to pass emissions without cats feel free to chime in. thanks