P0411 on Subaru
Secondary Air Injection System Incorrect Flow Detected
P0411 on Subaru vehicles indicates secondary air injection system incorrect flow detected. Au7o has documented this code across 1 Subaru model — most commonly on WRX. This emissions code means the secondary air injection system is flowing an incorrect amount of air. That system pumps fresh air into the exhaust shortly after a cold start to help the catalytic converter heat up and burn off pollutants faster. The computer monitors the resulting change in exhaust oxygen readings, and sets this code when the measured airflow is too high, too low, or otherwise not what it commanded. It is primarily an emissions issue and often traces to the air pump, valves, or their plumbing. Typical repair costs on Subaru range from $700 to $2,200, depending on the specific model and root cause.
Common Causes of P0411
- •Failed secondary air injection pump
- •Stuck or faulty air switching/check valve
- •Carbon or moisture clogging the air passages
- •Leaking, cracked, or disconnected air hoses
- •Faulty pump relay or electrical wiring
- •Damaged or corroded connectors
- •Faulty vacuum control solenoid for the system
P0411 on Subaru by Model
Subaru WRX(1 issue)
- Secondary Air Injection Pump and Switching Valve Failure Triggering CEL and Limp Mode2006-2014
Turbo EJ255/EJ257 WRX models equipped with the secondary air injection system commonly develop failures of the air pump, pressure sensor, or the air switching valves. Moisture intrusion and corrosion can cause the valves to stick or the pump to seize, which sets emissions faults and on many cars can reduce power or force a limp-home condition. Owners typically report a check-engine light shortly after cold start, often with rough cold operation or an audible pump noise before failure.
Looking for P0411 on a different make?
View P0411 across all makes →Frequently Asked Questions
What does P0411 mean on Subaru?▼
P0411 stands for "Secondary Air Injection System Incorrect Flow Detected." This emissions code means the secondary air injection system is flowing an incorrect amount of air. That system pumps fresh air into the exhaust shortly after a cold start to help the catalytic converter heat up and burn off pollutants faster. The computer monitors the resulting change in exhaust oxygen readings, and sets this code when the measured airflow is too high, too low, or otherwise not what it commanded. It is primarily an emissions issue and often traces to the air pump, valves, or their plumbing. On Subaru specifically, this code is documented across 1 model.
What causes P0411 on Subaru vehicles?▼
Common causes on Subaru: Failed secondary air injection pump, Stuck or faulty air switching/check valve, Carbon or moisture clogging the air passages, Leaking, cracked, or disconnected air hoses, Faulty pump relay or electrical wiring. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix P0411 on a Subaru?▼
Repair costs on Subaru range from $700 to $2,200, depending on the specific model and root cause.
Which Subaru models have P0411 documented?▼
Au7o has documented P0411 on 1 Subaru model: WRX.