The oxygen sensor installs on 2001-2003 Mazda Protege, 2002-2003 Mazda Protege5, 2004-2005 Suzuki Forenza and 2005 Suzuki Reno with the 2.0L I4 engine. It signals whether the exhaust is running rich or lean so the engine computer can trim fuel delivery. It uses a female square connector.

Walker Products 250-241126 Oxygen Sensor Features:

• Fits 2001-2003 Mazda Protege; 2002-2003 Mazda Protege5; 2004-2005 Suzuki Forenza; 2005 Suzuki Reno with the 2.0L I4 engine
• Sensor locations by application: B1S1, B1S2 (bank and sensor number)
• Used in both upstream and downstream positions, depending on application
• 4-wire narrow-band oxygen sensor
• Built-in heater for fast warm-up
• M18x1.5 threaded mounting with a 22 mm hex, 250 mm (9.8 in.) overall length
• Female square connector at the harness end
• Platinum electrode layer with a protective coating against combustion residue