NTK 24642 Oxygen Sensor - Downstream

NTK Direct Fit Oxygen Sensor 24642

NTK Direct Fit Oxygen Sensor 24642 is a heated, specific-fit downstream oxygen sensor built for direct replacement on a wide range of Subaru, Toyota, Mazda, and Scion applications. It is engineered for OE-style fit, form, and function, with a threaded mounting design and a 4-wire harness for straightforward replacement.

Compatible With Subaru BRZ, Subaru WRX STI, Toyota 86, Mazda CX-9, Mazda CX-5, and other listed downstream applications, this NTK oxygen sensor supports accurate exhaust monitoring on vehicles that require an original-equipment equivalent design.

Key Features

• Direct fit oxygen sensor for specific downstream applications
• Heated sensor design for faster operating temperature
• 4-wire configuration with 27.5 in. wiring harness length
• Threaded mounting type with 18 mm thread diameter
• OE-equivalent design for Subaru, Toyota, Mazda, and Scion fitments
• NTK part number 24642 for catalog and service reference

Product Details

NTK is known for oxygen sensor manufacturing across import and domestic vehicle coverage, and this Direct Fit Oxygen Sensor line is built around OE application data and ceramic technology control from raw material through finished sensor. Part number 24642 is a downstream sensor used on many Subaru models, including the BRZ and WRX STI, as well as the Toyota 86, Mazda CX-9, Mazda CX-5, and Scion FR-S. It also covers multiple Subaru Impreza, Legacy, Outback, Forester, Baja, and Saab 9-2X applications.

This part cross-references DENSO Auto Parts (e.g., 234-4445, 234-4446) for the same application.

What It Helps Address

• Check engine light related to downstream oxygen sensor faults
• Incorrect exhaust oxygen readings affecting fuel control
• Slow sensor response from a worn heated O2 sensor
• Emissions test failures tied to sensor performance
• Driveability issues caused by degraded exhaust feedback

Installation Notes and Tips

Verify the vehicle’s year, make, model, and downstream sensor location before ordering. This sensor uses a threaded mounting style and a 4-wire harness, so connector match and harness routing should be checked against the original part. Confirm the exact position notes for Subaru Legacy and Outback California-emissions applications, since several downstream locations are listed for those vehicles.

Fits 2021 Subaru WRX STI, downstream. Fits 2013-2020 Subaru BRZ, downstream. Fits 2017-2020 Toyota 86, downstream. Fits 2016-2018 Mazda CX-9, downstream. Fits 2017 Mazda CX-5, downstream. Fits 2013-2016 Scion FR-S, downstream. Fits 2002-2014 Subaru Impreza, downstream. Fits 2005-2012 Subaru Legacy, downstream. Fits 2001-2012 Subaru Outback, downstream. Fits 2004-2010 Subaru Forester, downstream. Fits 2005-2006 Saab 9-2X, downstream. Fits 2004-2006 Subaru Baja, downstream.

Quality Assurance

NTK manufactures oxygen sensors to meet or exceed OE specifications and tests them extensively during production for quality and reliability. As part of the NGK family of products, NTK supports import and domestic coverage with OE application technology and direct-fit replacement design.