I have a Audi 2001 A4 Quattro and My check engine light came on and I have a code reader and two codes came up P491 and P492 which stands for secondary air system bank one and secondary air system bank two. How do I fix these problems? How much is it going to cost me? And is it necessary to fix immediately? Thank you for your help
Since it is affecting both banks. Look for a common problem.
- Secondary Pump Relay (not working)
- Secondary Air Pump Fuse (burnt/blown)
- Secondary Air pump (seized/broken)
- Vacuum Solenoid for Combi Valves (not working)
- Vacuum Leak in Combi Valve hoses.
June, 17, 2012 AT 9:55 PM
Secondary Air Injection components: #1 - air pump
#11 & #12 - combi valves
#26 - vacuum solenoid
Relay Location: (fuse is in the same area)
June, 18, 2012 AT 1:26 AM
The lines clog up on occasion and the valves fail as well. The system needs to be checked to make sure the pump is working, lines are clear, solenoids are working and the passages to the head are clear.
Cannot estimate anything till we know the exact failure.