The oxygen sensor installs in the upstream position on select 2015-2019 Audi and Volkswagen applications. It measures the exhaust air-fuel ratio across a broad range so the engine computer can meter fuel precisely. A built-in heater brings the element to operating temperature quickly after a cold start.

Walker Products 250-25115 Oxygen Sensor Features:

• Fits 2015-2016 Audi A3; 2015-2018 Volkswagen Golf; 2015-2019 Volkswagen Golf SportWagen; 2017-2019 Volkswagen Golf Alltrack; 2019 Volkswagen GTI
• Engine coverage includes 1.8L I4, 2.0L I4 applications
• Sensor location by application: B1S1 (bank and sensor number)
• 5-wire wide-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 oblong connector at the harness end with 5 spade terminals
• Platinum electrode layer with a protective coating against combustion residue