For concerns with the secondary air injection system on 2009 and later Volkswagen Jetta SportWagens equipped with the 2.5L engine, make sure that the combi-valve has been tested thoroughly. The combi-valve can be tested using the output diagnosis in address 01 0 engine electronics (ECM).
The following fault codes may be stored in the ECM:
P0491 (secondary air injection system Bank 1 insufficient flow)
P2431 (secondary air injection system air flow/pressure, Bank 1 sensor circuit)
P2432 (secondary air injection system air flow/pressure, Bank 1 sensor circuit low)
P2433 (secondary air injection system air flow/pressure, Bank 1 sensor circuit high intermittent)
Check that the combi-valve moves through the full range of motion on visual inspection with a mirror and light source, while running the output test with key-on-engine-off. Replace the valve if it does not complete the full range of motion during the test.
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