A-Premium Downstream O2 Oxygen Sensor for Nissan & Infiniti — Heated 4-Wire Single Pack

A-Premium Downstream O2 Oxygen Sensor is a direct-fit, heated 4-wire replacement sensor designed to restore correct downstream exhaust oxygen readings on compatible Nissan and Infiniti V6/L4 models.

This aftermarket downstream oxygen sensor from A-Premium is engineered to match the electrical and mounting specifications of many Nissan and Infiniti vehicles, including select Altima, 370Z, Q50, Q60, Q70, QX models and others. It uses a threaded, heated 4-wire design for rapid warm-up and consistent signal transmission to the vehicle’s engine control system. The item ships individually in a box and is identified by common reference numbers 250-241106, 234-4535, 24167 and related OEM cross-references.

Which vehicles will this A-Premium downstream O2 sensor fit?

The A-Premium downstream sensor fits a range of Nissan and Infiniti models with specified engine sizes and production years. Fitment varies by downstream position (left/right/front/rear) and exact model/version; always confirm fit with your vehicle details before ordering. Below are the primary compatible applications listed for this part.

• Infiniti Q40 (2015) and Q50/Q60 (2014–2015) with V6 3.7L engines.
• Infiniti Q70/Q70L (2014–2019) and QX50/QX70 (2015–2017) V6 3.7L models for downstream LH/RH.
• Nissan 370Z (2014–2020) V6 3.7L and Altima (2013–2018) L4 2.5L downstream applications (B1S2 noted).
• Additional fits include Juke, JX35, QX60, Pathfinder, Murano, Quest and Altima V6 variants—see product note for position-specific compatibility.

How does this sensor match the original equipment specifications?

This A-Premium unit is built as a threaded, heated oxygen sensor with a female connector and four wires to match OEM electrical connections. The heated element shortens warm-up time and helps the sensor reach operating temperature faster for reliable downstream readings. The threaded mounting and connector gender align with factory hardware for a straightforward swap.

• Wire count: 4 (heated sensor wiring compatible with factory harness).
• Mounting: standard threaded housing for direct replacement.
• Connector: female plug designed to mate to OEM wiring harness.
• Packaging: single sensor shipped in a protective box for one-to-one replacement.

What should I check before buying to avoid returns?

Because this part covers many model years and downstream positions, verify exact match to your vehicle’s part position and connector type before purchase. Use the seller’s vehicle compatibility tool (for example, Amazon Confirmed Fit) and read the product note thoroughly. If the note or confirmed fit result doesn’t match your VIN, don’t proceed to avoid installation problems or returns.

• Confirm the sensor position (downstream LH/RH, front, rear) required by your vehicle.
• Cross-check reference numbers: 250-241106, 234-4535, 24167, 226A01KC0A, etc.
• Compare connector gender and wire count with your existing sensor plug.
• When in doubt, provide your VIN to a mechanic or use an OEM parts lookup.

How will replacing the downstream oxygen sensor impact my vehicle?

Replacing a faulty downstream O2 sensor restores accurate post-catalyst oxygen readings to the engine control module, which helps the vehicle maintain proper fuel trims and emissions monitoring. While downstream sensors are not typically used for fuel mixture control like upstream sensors, they play an important role in emissions system diagnostics and catalytic converter performance monitoring.

• Helps maintain correct emissions monitoring and diagnostic feedback.
• Provides stable downstream lambda readings for the vehicle’s ECU.
• Matches OEM form factor to simplify installation and minimize wiring issues.

Who is this for: This A-Premium downstream oxygen sensor is intended for owners or technicians replacing a downstream O2 sensor on compatible Nissan and Infiniti models listed above. It's suited for DIY mechanics familiar with exhaust-sensor replacement, as well as repair shops looking for an affordable aftermarket direct-fit alternative. Always verify fitment for your specific vehicle and model year before purchase to ensure proper compatibility.