Hey guys im looking for some help, My o2 sensor gave me a CEL a few weeks ago, I took it to a garage and they ordered a new sensor, but they would not be able to get it fitted for a week (i drive about 100 miles a day) so i asked if it was ok to drive they said yes, so i did but my Cat broke near the end of the week so i ordered a Berk hi flow cat and got them to fit it at the same time as doing the o2 sensor all was fine then for a few days but then the CEL came back P0137 - O2 Sensor Circuit Low Voltage (Bank 1 - Sensor 2) any one no what i can do to fix this i have bought a spacer for the sensor but i'm not sure if thats the problem?

 

im guessing you have an AP2 most likely an 06+. its a hit or miss with HFC and CEL with the later model Ap2. i found that my O2 sensor was getting covered in water. and it would throw a code. i was going to drill out the hole in the space where the o2 goes to let the water drain. but i have gotten a flash pro and tune so i shut off my o2 sensor.