The 4-wire narrow-band oxygen sensor is a replacement sensor for 1999-2004 Land Rover Discovery, 1999-2002 Land Rover Range Rover and 2001-2004 Land Rover Freelander in the upstream position. It signals whether the exhaust is running rich or lean so the engine computer can trim fuel delivery. A built-in heater brings the element to operating temperature quickly after a cold start.

Walker Products 350-34462 Oxygen Sensor Features:

• Fits 1999-2004 Land Rover Discovery; 1999-2002 Land Rover Range Rover; 2001-2004 Land Rover Freelander
• Engine coverage includes 2.5L V6, 4.0L V8, 4.6L V8 applications
• 4-wire narrow-band oxygen sensor
• Built-in heater for fast warm-up
• M18x1.5 threaded mounting with a 22 mm hex, 470 mm (18.5 in.) overall length
• Female square connector at the harness end
• Platinum electrode layer with a protective coating against combustion residue