A-Premium Downstream O2 Oxygen Sensor Compatible with Nissan & Infiniti — 4‑Wire Heated, 400mm (250-241255)

The A-Premium downstream heated O2 oxygen sensor (part 250-241255) replaces the factory sensor to restore accurate post-catalytic converter exhaust readings for compatible Nissan and Infiniti models.

Designed as a direct-fit downstream (post-cat) replacement, this A-Premium oxygen sensor provides a four-wire, heated design with a 400 mm harness and threaded mount for straightforward installation. It is manufactured to meet common OEM fitment points for many Nissan and Infiniti vehicles produced between 2018 and 2024, and it ships in protective boxed packaging with a one-year unlimited-mileage warranty.

Which vehicles is this oxygen sensor compatible with?

This downstream sensor supports multiple Nissan and Infiniti applications across model years and engine types. Exact fit depends on position (rear/front/left/right) and engine code—consult the listed fitment details or your VIN to confirm compatibility.

• Nissan Altima: 2019–2021 L4 2.0L (B1S2, KR20DDET); 2022–2024 L4 2.0L/2.5L
• Nissan Kicks: 2018–2021 & 2022–2024 L4 1.6L (B1S2, HR16DE)
• Nissan Sentra: 2020–2024 L4 2.0L
• Nissan Versa/Versa Note: various 2018–2024 L4 1.6L fitments (B1S2, HR16DE)
• INFINITI QX50/QX55: 2019–2024 L4 2.0L (B1S2)
• Nissan Pathfinder, TITAN, TITAN XD: specific downstream/front/rear or left/right positions for 2020 models and later V6/V8 engines

What are the key technical specifications I should know?

The sensor is a heated, threaded oxygen sensor with a female connector and four wires. It arrives in a box and includes one sensor; overall harness length is 400 mm—sufficient for the intended factory routing on compatible vehicles.

• Reference numbers: 250-241255, 250241255
• Wire count: 4; connector gender: female
• Overall harness length: 400 mm; mounting: threaded
• Sensor type: heated O2 sensor; package: single sensor in a box

How does installation and performance look for a downstream replacement?

Installation is typically straightforward for anyone comfortable working under the vehicle or with a professional mechanic; the sensor uses a threaded mount and standard four-pin connector. As a downstream sensor, it monitors post-catalytic converter oxygen levels—useful for diagnostic readings and emissions system monitoring.

• Threaded mounting fits factory O2 sensor ports—no cutting or splicing required when matched correctly
• Four-wire heated design helps faster warm-up for accurate readings under many conditions
• 400 mm harness length is intended for OEM routing; check reach before installation
• Boxed packaging protects the sensor during shipping and storage

Who is this for? Automotive DIYers, independent technicians, and fleet managers who need a reliable downstream oxygen sensor replacement for supported Nissan and Infiniti models will find this A-Premium part useful. It’s intended for people replacing failed post-catalytic sensors, addressing check engine codes related to downstream oxygen signals, or restoring correct emissions monitoring after repairs. Always verify part compatibility with your vehicle’s year, engine code, and exact sensor position before purchase.