Secondary Air Injection System
Overview
- The Secondary Air Injection (AIR) system controls emissions during the first 20 to 120 seconds of engine operation by forcing air downstream into the exhaust manifolds to oxidize the hydrocarbons and carbon monoxide created by running rich at start up.
Troubleshooting
📎 Secondary Air Injection, P2440 | Bad Pump | Buick LaCrosse
- Test. Watch O2 readings
- O2 sensor should go lean when the air pump is working. If it’s not, check cut-off valve.
- Test Air System Switching Valve
- P2441 P2443 Secondary Air System Switching Valve Stuck Closed Bank 1, 2
- Check power and ground to the valve
- Try to operate valve manually
- Listen to the clicking sound. If really stuck, it won’t click.
- Start the car and listen to the irregularity in rpm while operating the valve.
- P2441 P2443 Secondary Air System Switching Valve Stuck Closed Bank 1, 2