This 4-wire narrow-band oxygen sensor fits 1996-1999 BMW 318i, 318is, 318ti, 1998-2001 BMW 750iL and 2000-2003 BMW X5 in the downstream position and 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 350-34512 Oxygen Sensor Features:

• Fits 1996-1999 BMW 318i, 318is, 318ti; 1998-2001 BMW 750iL; 2000-2003 BMW X5
• Engine coverage includes 1.9L I4, 4.4L V8, 4.6L V8, 5.4L V12 applications
• Sensor location by application: B1S2 (bank and sensor number)
• 4-wire narrow-band oxygen sensor
• Built-in heater for fast warm-up
• M18x1.5 threaded mounting with a 22 mm hex, 740 mm (29.1 in.) overall length
• Female circle connector at the harness end
• Platinum electrode layer with a protective coating against combustion residue