Well i picked an afternoon project of getting my truck ready and inspected and hopefully ill get around to putting the valence back on too.

I just used a scanner at oreilys and its showed no codes but showed that 6 out of 7 of the emissions readiness checks were passed. The evap system was shown as not passing.

My muffler got ripped off my last offroading adventure so ive been running stright pipes. Would this cause this issue? If not what do i need to try to fix this. and does anyone one know the driving cycle for this scan? I just picked up a new muffler that i am heading out to put on right now.