Hey everyone, I'm new to Audi forums and will have tons of questions. My biggest concern right now is taking care of a few things with my 2001 A6 4.2. I just purchased it about a week ago and I have a bluetooth obdII diag tool i use and it pulled these codes. I'm currently working on the o2 sensor codes at the moment but would like to get the others figured out as well. Everything leads to the o2 sensors being bad... But, these things are $150 a piece for oem replacements! Is there any way I could do damage to the engine by not having o2 sensors and replacing them with an 02 delete piggy back harness?

I'm getting these codes
P0501 Vehicle speed sensor Range/Performance (My speedometer does not work, im assuming because of this)

P0491 Secondary Air injection System (Bank 1)
P0492 Secondary air injection system (Bank 2)
P0116 Power train engine coolant temperature circuit range performance problem

P0150 02 sensor Bank 2 sensor 1
P1296 Powertrain
P0130 Bank 1 sensor 1

 

First thing is to clear all the codes and then see which ones come back. You just got the car and some may be old codes that were never cleared after prior issues. Try that and let us know what returns and those will be the ones to deal with.