The downstream oxygen (O2) sensors for the 2016–2020 Honda Fit (1.5L) and the 2016–2020 Honda Civic (1.5L Turbo) are not the same part. While both engines share a 1.5-litre displacement, the Civic features a turbocharged setup, requiring completely different exhaust configurations, sensor shapes, and electrical harness lengths.Here is the exact breakdown of the original equipment manufacturer (OEM) part numbers and top-tier aftermarket alternatives from trusted brands like Denso and Bosch.2016–2020 Honda Fit (1.5L Naturally Aspirated)The downstream sensor (Sensor 2) on the Honda Fit checks the efficiency of the catalytic converter. It sits lower down along the exhaust pipe under the car.Honda OEM Part Number: 36532-5R0-004Denso Interchange: 234-4978 (Denso is the original supplier for Honda)Bosch Interchange: 15741Connector Type: 4-wire20