can someone tell me which sensor/s I need to replace? here are my code errors:

PO 134 02 CIRCUIT, BANK 1-SENSOR 1, NO ACTIVITY

PO 135 02 HEATER CIRCUIT, BANK 1 - SENSOR 1, MALFUNCTION

I have a 2001 Chevy Silverado, 4.8 liter

Thanks in advance!

 

bank one sensor one is the sensor on the left side of the motor (drivers side) closest to the engine......Sounds like you have a bad wire somewhere, either cut or pinched somewhere....check the harness when you are under there also