Secondary Air Injection Pump
An electric pump that forces fresh air into the exhaust for the first minute or two after a cold start, so unburnt fuel in the cold rich exhaust continues burning and the catalytic converter reaches operating temperature sooner. It runs briefly and only when cold, so its failure is almost never noticed by a driver — but the loud whirring it makes after a cold start is a useful diagnostic in itself, by its presence or absence. Frequently destroyed by exhaust gas or condensate reaching it through a failed check valve, which is why replacing the pump alone tends to buy a second failure.
Also known as: air pump, smog pump, sai pump, secondary air pump, air injection pump
Referenced by 32 codes
Codes involving this component (32)
- P2444 Secondary Air Injection System Pump Stuck On Bank 1 High
- P2446 Secondary Air Injection System Pump Stuck On Bank 2 High
- P0410 Secondary Air Injection System A Moderate
- P0411 Secondary Air Injection System A Incorrect Flow Detected Moderate
- P2257 Secondary Air Injection System Control A Circuit Low Moderate
- P2258 Secondary Air Injection System Control A Circuit High Moderate
- P2259 Secondary Air Injection System Control B Circuit Low Moderate
- P2260 Secondary Air Injection System Control B Circuit High Moderate
- P2423 HC Adsorption Catalyst Efficiency Below Threshold Bank 1 Moderate
- P2430 Secondary Air Injection System Air Flow Pressure Sensor Circuit Bank 1 Moderate
- P2431 Secondary Air Injection System Air Flow Pressure Sensor Circuit Range/Performance Bank 1 Moderate
- P2432 Secondary Air Injection System Air Flow Pressure Sensor Circuit Low 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
- P2435 Secondary Air Injection System Air Flow Pressure Sensor Circuit Bank 2 Moderate
- P2436 Secondary Air Injection System Air Flow Pressure Sensor Circuit Range/Performance Bank 2 Moderate
- P2437 Secondary Air Injection System Air Flow Pressure Sensor Circuit Low 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
- P2441 Secondary Air Injection System Switching Valve Stuck Closed Bank 1 Moderate
- P2443 Secondary Air Injection System Switching Valve Stuck Closed Bank 2 Moderate
- P2445 Secondary Air Injection System Pump Stuck Off Bank 1 Moderate
- P2447 Secondary Air Injection System Pump Stuck Off Bank 2 Moderate
- P2448 Secondary Air Injection System High Air Flow Bank 1 Moderate
- P2449 Secondary Air Injection System High Air Flow Bank 2 Moderate
Other components in Exhaust and Emissions
- Oxygen Sensor 326
- EGR Valve 150
- Catalytic Converter 142
- NOx Sensor 118
- Reductant Injector 107
- Exhaust Gas Temperature Sensor 95
- Reductant Tank 95
- Diesel Particulate Filter 76
- SCR Catalyst 65
- EGR Cooler 62
- Exhaust Gas Differential Pressure Sensor 58
- Fuel Tank Pressure Sensor 58
- Exhaust Pressure Control Valve 56
- Reductant Heater 55
- Reductant Pump 51
- EVAP Vent Valve 43
- Exhaust Aftertreatment Fuel Injector 42
- Charcoal Canister 33
- EGR Position Sensor 32
- Reductant Temperature Sensor 29
- EVAP Leak Detection Pump 29
- EVAP Purge Valve 27
- Particulate Matter Sensor 24
- Reductant Control Module 24
- Reductant Level Sensor 23
- Secondary Air Switching Valve 22
- EGR Temperature Sensor 21
- Secondary Air Check Valve 21
- Catalyst Heater 20
- Catalyst Temperature Sensor 20
- Fuel Filler Cap 18
- EGR Cooler Bypass Valve 16
- Reductant Quality Sensor 16
- Exhaust Back Pressure Sensor 15
- Purge Flow Sensor 13
- Direct Ozone Reduction Catalyst 13
- EGR Vacuum Solenoid 9
- Fuel Vapour Temperature Sensor 5
- Fuel Additive Control Module 4
- Fuel Additive Tank 4
Information, not instruction
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