Secondary Air Injection System Air Flow/Pressure Sensor Circuit Range/Performance Bank 1
The secondary air injection system on Bank 1 is not delivering the correct air flow or pressure to the catalytic converter during cold start and warm-up cycles. This code indicates the air pressure sensor is detecting an out-of-range signal, preventing proper emissions control operation.
What You Might Notice
- Engine stalling at idle or during cold start
- Engine may have difficulty starting
- Secondary air injection pump making noise or grinding sounds
- Poor engine performance during acceleration
- Check Engine Light illuminated
Most Common Causes
- 1
Defective secondary air injection pump
The air pump may have internal wear, cavitation, or bearing failure preventing adequate air pressure delivery to the system.
- 2
Faulty air pressure sensor
The sensor may be sending an incorrect voltage signal to the PCM, causing it to interpret normal pressure as out-of-range.
- 3
Defective one-way check valve
A stuck or leaking check valve can prevent adequate air flow or allow backpressure, affecting system pressure readings.
- 4
Faulty air control solenoid valve or wiring issues
A defective solenoid, corroded connectors, or damaged wiring harness can prevent proper air flow control and pressure regulation.
How to Diagnose It
- 1
Check Defective secondary air injection pump — The air pump may have internal wear, cavitation, or bearing failure preventing adequate air pressure delivery to the system.
- 2
Check Faulty air pressure sensor — The sensor may be sending an incorrect voltage signal to the PCM, causing it to interpret normal pressure as out-of-range.
- 3
Check Defective one-way check valve — A stuck or leaking check valve can prevent adequate air flow or allow backpressure, affecting system pressure readings.
- 4
Check Faulty air control solenoid valve or wiring issues — A defective solenoid, corroded connectors, or damaged wiring harness can prevent proper air flow control and pressure regulation.
How to Fix It
- 1
Test and replace secondary air injection pump
Use a pressure gauge to verify pump output pressure. If pressure is below specification, replace the air pump assembly.
- 2
Inspect and replace air pressure sensor
Check sensor voltage output with a multimeter. If readings are erratic or out of specification, replace the sensor.
- 3
Inspect connectors and wiring harness
Visually inspect all secondary air injection system connectors for corrosion, damage, or loose connections. Clean corroded connectors with electrical contact cleaner and reseat connections.
- 4
Check and replace one-way check valve
Inspect the check valve for debris or wear. If the valve does not allow air flow in one direction only, replace it.
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