Oxygen Sensor for 2002-2005 Subaru Impreza & More - Walker 250-54004

Walker Products 250-54004 oxygen sensor for the 2002-2005 Subaru Impreza H4 2.0L and other vehicles measures the oxygen in the exhaust gas to monitor the air-fuel ratio for combustion efficiency. It is made for its specific application and upstream position, and it gives the ECU the diagnostic feedback it expects.

• Four-wire, wide-band air-fuel ratio sensor
• Monitors exhaust gases to help reduce pollutants
• Measures oxygen levels to help fine-tune the air-fuel mixture, which supports fuel economy
• Electrodes made of a gas-permeable platinum layer
• Electrode coating guards against contamination and erosion from combustion residue and particulates in the exhaust gas

Quick facts

• Part: Walker Products 250-54004 oxygen sensor
• Fits: 2002-2005 Subaru Impreza H4 2.0L and other vehicles
• Position: Upstream
• Condition: New

Rough running, higher fuel use, higher exhaust emissions or a lit malfunction indicator light can mean this oxygen sensor is worn, though a damaged wiring harness or connector can be behind the same signs, so look both over for physical damage first. Newer vehicles store fault codes in the ECU, and a shop can read them.

Fits

This oxygen sensor fits the 2002-2005 Subaru Impreza H4 2.0L and the 2005 Saab 9-2X H4 2.0L, with one sensor per car. This listing is a single sensor.

Specifications