The 3-wire narrow-band oxygen sensor is a replacement sensor for 1986-1994 Porsche 911, 1986-1989 Porsche 944 and 1988-1995 Porsche 928 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 350-33078 Oxygen Sensor Features:

• Fits 1986-1994 Porsche 911; 1986-1989 Porsche 944; 1988-1995 Porsche 928
• Engine coverage includes 2.5L I4, 3.2L H6, 3.3L H6, 3.6L H6, 5.0L V8, 5.4L V8 applications
• Sensor location by application: B1S1 (bank and sensor number)
• 3-wire narrow-band oxygen sensor
• Built-in heater for fast warm-up
• M18x1.5 threaded mounting with a 22 mm hex, 700 mm (27.6 in.) overall length
• Male/female circle connector at the harness end
• Platinum electrode layer with a protective coating against combustion residue