4Pcs Up&Downstream Oxygen Sensors Fits 2011-2014 Ford F-150 3.5L V6 Turbocharged Fit for: 2011-2014 Ford F-150 3.5L V6 Turbocharged Specifications: OE Numbers: 234-4490 234-5076 234-5113 Product Material: Stainless Steel Color: Black, Brass, Silver Installation Position: Upstream, Downstream Functions: 1. The Upstream oxygen sensor is used to Monitor Raw Exhaust Gas to Adjust Air-fuel Ratio in Real-time, i.e., it is used to Detect Whether the Exhaust Gas Exceeds the Standard. 2. The Downstream oxygen sensor is mainly used to Detect Whether the Three-way Catalytic Converter Works Normally. .
