I am getting a check engine light in my car took it to my buddys that has a vagcom
16815 - Warm Up Catalyst; Bank 2: Efficiency Below Threshold
P0431 - 35-00 - -
17863 - Exhaust Gas Temp Sensor 1 (G235): Implausible Signal
P1455 - 35-10 - - - Intermittent
17867 - Exhaust Gas Temp Sensor 2 (G236): Implausible Signal
P1459 - 35-10 - - - Intermittent
17539 - Oxygen (Lambda) Sensor; B2 S1: Internal Resistance too High
P1131 - 35-10 - - - Intermittent
17521 - Oxygen (Lambda) Sensor; B1 S1: Internal Resistance too High
P1113 - 35-10 - - - Intermittent
He was explaining how there are 2 o2 sensors and then the catalytic converter then 2 more o2 sensors. Could I only need to replace the front 2 and do you think then it would clear the back to, or is it just best to replace all 4 at once.
Bruce




