Hey, i got a
1999 Audi a6 2.8
95k miles

I am getting a check engine light on it and when i go to test it i get the codes:
P0158, P1198, P1199.
Ive replaced the O2 sensors, bought them brand new from dealer (both of them) and still have the errors.

Could any one give me any help / hints?

 

P0158 : O2 Sensor Circuit - High Voltage (Bank 2 Sensor 2)
- Faulty O2 sensor
- Short to battery voltage in O2 sensor signal circuit

P1198 :O2 Sensor Heater Circ.,Bank1-Sensor2 Electrical Malfunction

P1199 : O2 Sensor Heater Circ.,Bank2-Sensor2 Electrical Malfunction

Assuming you replaced the correct 2 o2 sensors and not the front 2, then I would have to assume you have a wiring issue.

Bank 1 = passenger side
Bank 2 = drivers side
Sensor 1 = pre-cat
Sensor 2 = post-cat

Welcome to the forums.

 

Thanks for the info, i did not replace the left one on the back. what could i try doing next?