P0411: Secondary Air Injection System Incorrect Flow Detected
4 vehicles · 3 makes · $80-$4,000 repair
Most Reported On
P0411 is an OBD-II diagnostic trouble code meaning “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. This code is most commonly reported on 2005-2013 Toyota Tundra, 2001-2009 Toyota Sequoia, and 2006-2014 Subaru WRX, plus 1 other vehicle, with repair costs ranging from $80 to $4,000.
Common Causes
Typical Repair Cost
Based on 5 documented vehicle-specific issues. Actual cost depends on root cause and vehicle.
Diagnostic Tools
To diagnose P0411, you'll need an OBD-II scanner. Here are our recommendations at every price point.
ANCEL AD310 Classic OBD-II Scanner
by ANCEL
A simple, affordable code reader that reads and clears check engine codes. Great for quick diagnostics on any OBD-II vehicle (1996+).
- Read & clear engine codes
- View freeze frame data
- I/M readiness status
- No batteries or app needed
BlueDriver Pro Bluetooth Scanner
by BlueDriver
Bluetooth OBD-II scanner with a free companion app. Provides enhanced diagnostics, smog readiness, and repair reports sourced from a database of verified fixes.
- Enhanced diagnostics (ABS, SRS, transmission)
- Repair Reports with verified fixes
- Smog check readiness
- Free app (iOS & Android)
LAUNCH CRP123X OBD-II Scanner
by LAUNCH
A professional-grade handheld scanner that reads all four major systems (engine, transmission, ABS, SRS) with live data streaming and graphing.
- Engine, transmission, ABS, SRS diagnostics
- Live data stream & graphing
- AutoVIN for vehicle identification
- Free lifetime updates via Wi-Fi
Autel MaxiCOM MK808S Diagnostic Tool
by Autel
Shop-level diagnostic tablet with bi-directional control, active tests, and full system coverage. Ideal for serious DIYers and small shops.
- All-system diagnostics (25+ modules)
- Bi-directional control & active tests
- Oil reset, EPB, BMS, TPMS, injector coding
- 7-inch touchscreen with Android OS
As an Amazon Associate, we earn from qualifying purchases. Prices are approximate and may vary.
Vehicles Affected (4)
FAQ
What does P0411 mean?
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.
What are the most common causes of P0411?
The most common causes of P0411 are: 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. The specific cause varies by vehicle.
How much does it cost to fix P0411?
Repair costs for P0411 range from $80 to $4,000, depending on the vehicle and root cause.
Which vehicles are affected by P0411?
Au7o has documented P0411 across 4 vehicle models from 3 manufacturers: Audi, Subaru, Toyota.
Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.