What is the reason for the secondary air function failure in Audi A6L?
2 Answers
Audi A6L reporting secondary air function failure may be due to oxygen sensor or three-way catalytic converter malfunction. It is recommended to check the oxygen sensor and three-way catalytic converter at a 4S shop or repair shop. Common transmission faults in Audi A6L are manifested as no gear display in D gear or reverse gear during driving, or a red screen state, which causes the car to lock the gear and cannot shift up. The fault codes are communication faults or turbine speed sensor faults, etc. The following is an introduction to the new Audi A6L: 1. Launch time: The new Audi A6L is a car series developed by FAW-Audi on the basis of the new German A6 and is the replacement product of Audi A6. The car was launched on June 16, 2005. 2. Appearance: In terms of exterior design, compared with the previous generation Audi A6, the biggest change in the appearance of the new Audi A6L is that the heat dissipation and air intake grille, which were originally separated by the front bumper on the front face, have become a complete trapezoidal grille. 3. Power: The new Audi A6L is equipped with two efficient gasoline engines, 2.8FSI and 3.0TFSI. Among them, the 3.0TFSI engine is the latest top version of Audi's V6 engine. The perfect combination of gasoline direct injection and mechanical supercharging gives it power exceeding that of an 8-cylinder engine and extremely high fuel efficiency. It can output a maximum power of 213 kilowatts (290 horsepower) and a strong torque of 420 Nm.
I've repaired quite a few Audi cars in my lifetime, and the A6L reporting secondary air function failure is quite common, mostly caused by several mechanical issues. During cold engine starts, the system needs to inject fresh air into the exhaust to reduce pollution, but the valves are prone to getting stuck due to carbon buildup or dust, making them open and close improperly. Another common issue is the aging of the air pump—if it becomes noisy or the RPM becomes unstable, it can't function properly. Electrical control parts often malfunction too, such as short circuits in the control module's wiring or sensor signal drift, causing the system to receive incorrect commands and automatically report errors. Aging and cracked rubber hoses can also leak air, affecting system efficiency. I remember a car I repaired last month had a valve issue—replacing the part solved the problem. If not addressed promptly, it could lead to failing emission standards, trouble during annual inspections, or even adding extra burden to the engine. I recommend going to a 4S shop to check the diagnostic codes immediately, before other components get affected. In short, if you're handy, you can inspect it yourself, but for most car owners, it's better to seek professional repair.
