01 Mil On (DTC P0491/P0492 Secondary Air Injection System Bank 1/2 Insufficient Flow) (GROUP 01, NO. 17-10)
Reference number: GROUP 01, NO. 17-10
Supersedes refnos: 2035002, 2035002/4, 2035002/5, GROUP 01, NO. 13-25, GROUP 01, NO. 15-46, GROUP 01, NO. 15-47, GROUP 01, NO. 16-55
01 MIL ON (DTC P0491/P0492 SECONDARY AIR INJECTION SYSTEM BANK 1/2 INSUFFICIENT FLOW)
TECHNICAL SERVICE BULLETIN
| AUDI: | A8 2010 - 2012 |
| GROUP: | 01 - On-Board Diagnostic |
APPLICABLE MODELS AND YEARS
01 17 10 2035002/5 April 20, 2017. Supersedes Technical Service Bulletin Group 01 number 16-55 dated March 14, 2016 for reasons listed below.
| Model(s) | Year | VIN Range | Vehicle-Specific Equipment |
|---|---|---|---|
| A8 | 2010 - 2012 | All | 4.2FSI |
CONDITION
| REVISION HISTORY | ||
|---|---|---|
| Revision | Date | Purpose |
| 5 | - | Revised Required Parts and Tools
(Updated part number) Revised Service (Completely revised) |
| 4 | 03/15/2017 | Revised Required Parts and Tools (Updated part number) |
| 3 | 10/22/2015 | Revised Production Solution
(Added solution) Revised Service (Completely revised) Revised Warranty (Updated TU for GFF) Updated Required Parts and Tools (Removed parts; updated part numbers) |
- MIL on.
The following DTCs are stored in the engine control module (ECM), J623 (address word 0001):
- DTC P049100 (secondary air system bank 1, low flow)
- DTC P049200 (secondary air system bank 2, low flow)
TECHNICAL BACKGROUND
The DTCs may appear during monitoring of the secondary air system during the engine cold starting phase. With the electric solenoid valves controlled, a diagnosis cycle is performed and the secondary air pressure is measured for a specified value.
The air pressure can be influenced by several factors within the secondary air system or the vacuum system.
PRODUCTION SOLUTION
Improved combination valves.
SERVICE
Check the vacuum system for leaks
During the catalyst heating phase, the secondary air valves could close too early if vacuum supply is low. Low vacuum supply can be a result of a leak in the vacuum system, so it is necessary to check the entire system for leaks.
- Check the vacuum check valve for leaks (Figure 1). The direction of flow should only be towards the intake manifold.
If a leak is found at the check valve, replace the valve and recheck.
- With the hose to the check valve disconnected, apply 400 mmHG of vacuum with the VAS 6213 hand vacuum pump (Figure 2).
If the vacuum supply drops during the first 10 minutes of the test, check the complete vacuum system and solenoid changeover valves for leaks using the diagram below.
See diagram (Figure 3):
- Cylinder Bank 1 Intake Manifold Flap Vacuum Actuator
- Cylinder Bank 2 Intake Manifold Flap Vacuum Actuator
- Intake Manifold Runner Control Valve N316
- Left Secondary Air Injection (AIR) Combination Valve
- Right Secondary Air Injection (AIR) Combination Valve
- Cylinder Head Coolant Valve N489 - Vacuum Actuator
- Secondary Air Injection Solenoid Valves N112 and N320
Repair as necessary.
- 4. If the engine warning light has come on in combination with DTC P049100 and/or DTC P049200, proceed as follows after the vacuum system was checked and with the procedure listed above.
- 5. Replace the following components:
- Bank 1 and Bank 2 - Combination valves and gaskets (079 131 101 AN and 06A 131 120 D )
- Secondary air injection sensor 1 (G-609) (06K 906 052 ). SAI solenoid valves N112 and N320 for combination valves (037 906 283 C )
- Delete the DTC entry before setting the readiness code.
If the DTC is not logged after two engine starts, return the vehicle to the customer.
Check the exhaust catalyst
Only perform this section if the vehicle has a history of prior misfire or catalyst efficiency DTC.
Vehicles with misfire DTCs (e.g., P0300, P0301 - P0308, or P130A) or faulty catalyst DTCs (e.g., P042100 or P043100) in current or older diagnosis protocols may have faulty exhaust catalysts.
- Remove pre and post oxygen sensors and endoscope the catalysts from both ends and assess the honeycomb structure for damage.
- If damage is found, repair as necessary.
WARRANTY
| Claim Type: |
|
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| Service Number: | 2640 | ||
| Damage Code: | 0010 | ||
| Labor Operations: | Combi valves remove + reinstall (both) | 2640 2019 | 40 TU |
| Secondary Air Solenoid Valves N112/N320 remove + reinstall both | 2644 1999 | 40 TU | |
| Pressure sensor G609 remove + reinstall | 2675 1919 | 20 TU | |
| Front heated oxygen sensors remove + reinstall both | 2469 2019 | 130 TU | |
| Rear oxygen sensors remove + reinstall both | 2473 2019 | 90 TU | |
| Borescope check of both exhaust catalysts | 2640 0299 | 30 TU max | |
| Vacuum system checks | 2640 0299 | 30 TU max | |
| Diagnostic Time: | GFF | 0150 0000 | Time stated on diagnostic protocol (50 TU max) |
| Road test prior to service procedure | No allowance | 0 TU | |
| Road test after service procedure | 0121 0004 | 10 TU | |
| Technical diagnosis at dealer's discretion (Refer to Section 2.2.1.2 and Audi Warranty Online for DADP allowance details) |
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| Claim Comment: | As per TSB #2035002/5 | ||
All warranty claims submitted for payment must be in accordance with the Audi Warranty Policies and Procedures Manual . Claims are subject to review or audit by Audi Warranty.
REQUIRED PARTS AND TOOLS
| Part Number | Part Description | Quantity |
|---|---|---|
| 06K 906 052 | Secondary air injection sensor (G609) | 1 |
| 06A 131 120 D | Combination valves gaskets | 2 |
| 079 131 101 AN | Combination valves for secondary air system | 2 |
| 037 906 283 C | Solenoid valves N112/N320 for operating combination valves | 2 |
| Tool Number | Tool Description |
|---|---|
| VAS 6213 | Hand Vacuum Pump |
| 3337 | Ring Spanner 7 piece set for oxygen sensor removal (if required). |
ADDITIONAL INFORMATION
All parts and service references provided in this TSB (2035002) are subject to change and/or removal. Always check with your Parts Department and service manuals for the latest information.
