red1bw

The B8 S4 now has 110K miles on her. The MIL light came on and shows codes P0491 & P0492 which are codes for Secondary Air Injection System Insufficient Flow Bank 1 and Bank 2 respectively. I've started to get smart on this area and there isn't too much on solutions for these codes for B8's.
I would also like to note that 19 days before the MIL lit up I had just replaced the thermostat on this car - that means removal of the TB/Supercharger and a bunch of other stuff...but everything was put back (and double-checked) and the car was driven daily for those 19 days with no issues.
I will update later with a VCDS scan, but I expect scan will basically show the same. So anyone have any ideas on this as far as what would make both P0491 and P0492 come on at the same time, and any tricks for knowing how to test is the pump running or what part may have been jarred loosed during a thermostat change?
Thanks.

red1bw

VIN: WAUKGBFL8AAXXXXXX Mileage: 178190km-110722miles

01-Engine -- Status: Malfunction 0010
02-Auto Trans -- Status: OK 0000
03-ABS Brakes -- Status: OK 0000
04-Steering Angle -- Status: OK 0000
05-Acc/Start Auth. -- Status: OK 0000
08-Auto HVAC -- Status: OK 0000
09-Cent. Elect. -- Status: OK 0000
10-Park/Steer Assist -- Status: OK 0000
14-Susp. Elect. -- Status: OK 0000
15-Airbags -- Status: OK 0000
16-Steering wheel -- Status: OK 0000
17-Instruments -- Status: OK 0000
19-CAN Gateway -- Status: OK 0000
1B-Active Steering -- Status: OK 0000
22-AWD -- Status: OK 0000
36-Seat Mem. Drvr -- Status: OK 0000
3C-Lane Change -- Status: OK 0000
42-Door Elect, Driver -- Status: OK 0000
46-Central Conv. -- Status: OK 0000
47-Sound System -- Status: OK 0000
52-Door Elect, Pass. -- Status: OK 0000
53-Parking Brake -- Status: OK 0000
55-Headlight Range -- Status: OK 0000
56-Radio -- Status: OK 0000
5F-Information Electr. -- Status: OK 0000
62-Door, Rear Left -- Status: OK 0000
6C-Back-up Cam. -- Status: OK 0000
72-Door, Rear Right -- Status: OK 0000

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Address 01: Engine (J623-CCBA) Labels: 06E-907-551-CAK.clb
Part No SW: 8K0 907 551 A HW: 8K0 907 551 A
Component: 3.0T SIMOS84 H06 0002
Revision: --------
Coding: 0104000A240F0128
Shop #: WSC 06325 000 00000
ASAM Dataset: EV_ECM30TFS8K0907551A A01003
ROD: EV_ECM30TFS8K0907551A.rod
VCID: 2F88C833A623D4EDD4E45E-807A

2 Faults Found:
8931 - Secondary Air Injection System: Bank 1
P0491 00 [232] - Insufficient Flow
MIL ON - Intermittent - Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 14
Mileage: 168754 km
Date: 2015.05.22
Time: 07:49:44

8932 - Secondary Air Injection System: Bank 2
P0492 00 [232] - Insufficient Flow
MIL ON - Intermittent - Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 14
Mileage: 168754 km
Date: 2015.05.22
Time: 07:49:44

Readiness: 0000 0000

-------------------------------------------------------------------------------

red1bw

I brought the car in to the Audi dealer (first time) with 112K miles along with a copy of the warranty extension for the Secondary Air Injection. The dealer gave me a brand new Q5 as a loner for 4 days while they cleaned the SAI's with the Powerwash method. Total cost 0$.
So with this car doing 60% highway and 40% local driving, I shouldn't have to worry about carbon clogging these ports again for another 5.5 years and 110K more miles from an emissions standpoint.