NTK 21565 Oxygen Sensor - Downstream Left or Downstream Right

Direct Fit Oxygen Sensor for OE Applications

The NTK 21565 is a direct fit oxygen sensor built for specific applications and engineered to match OE fit, form, and function. It uses a heated, threaded design with a 4-wire configuration and a 32.5-inch harness for a precise replacement on supported vehicles.

Key Features

• Direct fit design for specific applications
• Heated oxygen sensor construction
• 4-wire configuration for OE-style signal control
• Threaded mounting type with 18 mm thread diameter
• 32.5-inch wiring harness length
• Extensively tested during manufacturing for quality and reliability

Detailed Description

NTK 21565 is part of the Direct Fit Oxygen Sensor line, developed to streamline replacement selection while maintaining OE-level application coverage. NTK combines ceramic manufacturing expertise with sensor technology to produce an oxygen sensor that supports accurate exhaust feedback and dependable operation. This part cross-references Bosch 15141 and DENSO Auto Parts 234-4338 for the same application. Compatible with Cadillac STS, Cadillac SRX, and Cadillac XLR applications, it is a direct replacement choice for downstream oxygen sensor service where the original sensor uses a threaded, heated configuration. The NTK 21565 is also referenced in OE-style service applications for Cadillac XLR downstream left and downstream right positions, as well as Cadillac STS and SRX downstream right positions.

What It Is Used For

• Replacing a worn or failed oxygen sensor
• Restoring exhaust gas feedback to the engine control system
• Addressing check engine light concerns related to sensor performance
• Correcting drivability issues caused by inaccurate air-fuel data
• Servicing downstream sensor locations on supported Cadillac applications

Installation Notes and Tips

Verify the connector style, harness length, thread diameter, and sensor location before installation. This part uses a threaded mounting type and a specific-fit design, so it should be matched to the original application details for proper installation. Confirm the vehicle position and notes in the fitment data before ordering.

Quality Assurance

NTK states that its oxygen sensors are extensively tested during manufacturing to help ensure quality and reliability that meet or exceed OE specifications. The brand is part of the NGK family and is recognized as a major OE oxygen sensor supplier.