P0411 - Secondary Air Injection Incorrect Flow

Secondary air injection flow not as expected.

Code Overview

Secondary air injection flow not as expected.

Common Causes

• Air hoses leak
• Pump weak
• Check valve stuck
• Vacuum control issue

Diagnostic Steps

1. Inspect air plumbing
2. Verify pump output
3. Check valves
4. Check vacuum controls

Likely Repairs & Cost Guides

Use test results to confirm the fault before pricing the repair.

Related OBD Codes

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Next Steps

Move from the code to a diagnosis path, then into repair pricing once the fault is confirmed.