can p0136 cel code for o2 sensor effect my performance?

ive been getting this code for about 3 weeks now...been thinkin bout going with the spark plug non foulers trick but i dont have to pass emissions so i dont know if its worth the trouble right now...it didnt throw any other codes but it has before like misfiring on a couple cylinders...Any advice would help...thanks

 

Did you do any mods recently before the cel? If nothing probably just a bad sensor.

 

oh yessir!...the usual...vf34,fmic,4 inch downpipe with 4 inch cat delete to hks high power,cobb accessport,565 injectors and so on...but that was all done bout 10k miles ago and never had a cel code till bout 3 weeks ago

 

Probably a bad sensor, no?

 

Couple possibilities, but yes probably a bad o2 sensor or frayed wiring.