Cause
Faulty secondary air flow sensor
The sensor confirming that pumped air actually reached the exhaust. It normally reports a genuine flow problem rather than failing itself — a seized pump, a blocked pipe or a stuck check valve — so it is the last thing on this list rather than the first.
Typically a moderate job.
Codes this can cause (10)
Codes where this is a likely explanation first, rather than merely a possible one.
- P2430 Secondary Air Injection System Air Flow Pressure Sensor Circuit Bank 1 Likely for this code Moderate
- P2432 Secondary Air Injection System Air Flow Pressure Sensor Circuit Low Bank 1 Likely for this code Moderate
- P2435 Secondary Air Injection System Air Flow Pressure Sensor Circuit Bank 2 Likely for this code Moderate
- P2437 Secondary Air Injection System Air Flow Pressure Sensor Circuit Low Bank 2 Likely for this code Moderate
- P2431 Secondary Air Injection System Air Flow Pressure Sensor Circuit Range/Performance Bank 1 Moderate
- P2433 Secondary Air Injection System Air Flow Pressure Sensor Circuit High Bank 1 Moderate
- P2434 Secondary Air Injection System Air Flow/Pressure Sensor Circuit Intermittent/Erratic Bank 1 Moderate
- P2436 Secondary Air Injection System Air Flow Pressure Sensor Circuit Range/Performance Bank 2 Moderate
- P2438 Secondary Air Injection System Air Flow Pressure Sensor Circuit High Bank 2 Moderate
- P2439 Secondary Air Injection System Air Flow/Pressure Sensor Circuit Intermittent/Erratic Bank 2 Moderate
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