The 4-wire narrow-band oxygen sensor is a replacement sensor for select 2003-2018 Buick, Cadillac, Chevy, GMC and other applications. 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 350-34551 Oxygen Sensor Features:

• Fits 2012-2014 Buick Verano
• Fits 2003-2006 Cadillac Escalade, Escalade ESV, Escalade EXT, Chevy Avalanche 2500, Silverado 1500, Silverado 1500 HD, Silverado 2500 HD, Silverado 3500, Suburban 2500, GMC Sierra 1500
• Also fits select Buick, Cadillac, Chevy, GMC, Hummer and Saab applications
• Sensor locations by application: B1S1, B1S2, B2S1, B2S2 (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, 380 mm (15 in.) overall length
• Male trapezoid connector at the harness end
• Platinum electrode layer with a protective coating against combustion residue