O2 Sensor for Subaru Impreza WRX Front Upstream Lambda Air Fuel Ratio Sensor Replacement
Upgrade your Subaru’s oxygen sensing with this Front Upstream Air Fuel Ratio Lambda O2 Sensor, designed to deliver precise, real-time feedback to the engine control unit. This heated, 4‑wire sensor plays a crucial role in maintaining the ideal air-fuel mixture, helping your WRX respond swiftly to throttle input, improve fuel efficiency, and lower emissions. By accurately measuring the exhaust’s oxygen content before the catalytic converter, it ensures the ECU can adjust fuel delivery quickly and accurately, even during cold starts and under varying driving conditions.
Crafted for Subaru performance models, this upstream sensor is a direct-fit replacement that supports consistent idle stability, smoother acceleration, and more reliable catalytic converter operation. With compatible part numbers 22641-AA220, 22641AA220, 22641AA390, 22641AA391, and 22641-AA391, it aligns with a wide range of Impreza WRX/ STI variants (GDA/GDB) and related Legacy and Touring Wagon models. The heating type accelerates warm-up, reducing rich fuel trims during cold starts and helping your vehicle reach optimal operating temperature faster.
All electronic and mechanical equipment, devices and machines sold by InterCyprus to EU countries are CE certified and carry a two year warranty.
Language support for this product: English is supported for ordering and documentation where available.
Benefits & Tips
- Boosts fuel efficiency and reduces emissions by ensuring the engine runs at the correct air-fuel ratio across operating conditions, especially after cold starts.
- Enhances throttle response and drivability by delivering reliable oxygen readings to the ECU, helping your WRX maintain optimal performance.
- Use as part of a routine maintenance upgrade when restoring or tuning older Impreza/Legacy models to preserve engine health and enable accurate long-term fuel trims.
Product specifications
- Brand: Choice
- Sensor Type: Piezoelectric
- Type: Heating Type
- Measuring Range: Air Fuel Ratio Lambda O2 Oxygen Sensor
- Wire Quantity: 4
- OEM No.: 22641-AA220, 22641AA220, 22641AA390, 22641AA391, 22641-AA391
- Origin: Mainland China
- Fitment: Subaru Impreza WRX GDA (EJ207) 09/2003-06/2004; WRX GDA EJ207 (E/J) 06/2004-06/2005; WRX GDA EJ207 (F) 06/2005-06/2006; WRX GDA EJ207 (G) 06/2006-06/2007; Subaru Impreza WRX STI GDB EJ207 (D/E/F) 09/2003-06/2004; STI GDB EJ207 (E/F) 06/2004-06/2005; STI GDB EJ207 (F) 06/2005-06/2006; Subaru Legacy B4 BL5 EJ20Y (A/B/C) 04/2003-04/2006; Subaru Legacy Touring Wagon BP5 EJ20Y (A/B/C) 04/2003-04/2006
- Warranty: 2 years (Replacement Warranty)
- Part Number: 22641-AA220, 22641AA220, 22641AA390, 22641AA391, 22641-AA391
Package includes
- 1 pcs
Warnings/Reminders
Before ordering, please check product pictures, accessories and part numbers. If you are unsure, please send us a product picture or part number before ordering. To avoid wrong orders, read the purchase guide carefully.
Shipping and service notes: All items are dispatched within 2 working days after payment confirmation. Ensure your shipping address is correct. Import duties, taxes, and charges are not included in item price or shipping charges.
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