P2449 indicates that the secondary air injection system on bank 2 is delivering more airflow than the control module expects. The code is set when the air flow or pressure sensor reports a value above the calibrated threshold for a given operating condition.
The valve fails to close, allowing excess air into the exhaust stream.
The pump delivers higher flow than commanded by the PCM.
Unmetered air enters the system, raising measured flow.
Sensor reports a higher flow value than actual.
Damaged or corroded wiring causes an erroneous high‑flow signal.
Rare; only considered after all hardware checks are normal.
No, the PCM is rarely the cause; the code is usually triggered by a mechanical or sensor fault in the secondary air injection system.
The vehicle can be driven, but excess air injection can increase emissions and may cause a failed emissions test.
In many designs the valve is a replaceable component; cleaning may temporarily restore function but replacement is typical.
Clearing the code only resets the light; the underlying fault will cause the code to return until repaired.