p0136 code

getting p0136 code in my 03 tacoma, i replaced my downstream 02 sensor and reset . 60 miles later light back on same code, noticed exhaust leak right before cat, fixed that, reset waiting for results, gas milage better since rapla.cing o2 sensor. if light comes back on with same code is it my cat, and if i remove cat will light stay off and how will it run.

 

Had this code my self replaced down stream sensor. Took almost 200 miles for light to finally go out

 

Which sensor did you purchase the Bosch or Denso ? is your taco the four banger? auto or manual? what did you pay for this sensor/ thanks for any info and yes this is a old message