Secondary Air Injection System Stuck Off (Bank 1)
The secondary air injection system for bank 1 is not operating correctly.
Heads up: this code wasn't in our hand-written library yet, so DiagCoach AI built this page on the fly. Double-check critical specs against service info before condemning parts.
What it means (plain English)
The computer controls a pump that pushes air into the exhaust to help it burn cleaner but it's not working right, so exhaust emissions may be higher.
What the computer is actually seeing
The PCM expects the secondary air system to activate during cold starts. If it doesn’t see a designated pressure change in the system within a few seconds, or detects no change in the upstream O2 sensor readings, it sets this code.
What a healthy reading looks like
The system should show a pressure change: typically between 1.5 to 3.5 psi when the pump is active during the intended operation period, usually lasting 30-120 seconds after engine start.
Guided diagnostic — the DiagCoach way
Don't just throw parts at it. Walk through these in order — each step tells you whether to keep going or stop and fix what you found.
- 11. Inspect the wiring and connectors at the secondary air injection pump for visible damage or corrosion. Decision: If damaged, repair or replace.
- 22. Check the operation of the secondary air injection pump by applying direct battery voltage (12V). It should activate. Decision: If it does not activate, replace the pump; if it does, proceed to next step.
- 33. Check for air flow restrictions in the hoses and valves. Use a smoke test if necessary. Decision: If blocked, clear the obstruction; if clear, proceed to next step.
- 44. Read the real-time data from the upstream O2 sensor during a cold start. You should see it transitioning within the first 60 seconds. Decision: If no transitions, suspect a faulty O2 sensor; if transitions are normal, further diagnostics may be needed.
Common causes
- Failed secondary air injection pump
- Blocked air passages or valves
- Damaged wiring or connectors to the pump
- Faulty PCM
Typical repair cost
$$
Related codes
Frequently asked questions
Can I still drive the car with this code?
Yes, but expect higher emissions and potential drivability issues. Fix it soon.
Will this code come back after I clear it?
If the underlying issue isn’t fixed, it will reappear after a drive cycle.
Why does this relate to other codes?
Secondary air injection issues often accompany other emissions-related codes due to their interconnected systems.
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