NTK 21513 Oxygen Sensor

NTK Direct Fit Oxygen Sensor 21513

NTK 21513 is a direct fit heated oxygen sensor built for specific applications that require OE-style fit, form, and function. It uses a threaded mounting design, a 4-wire configuration, and a 15.75-inch wiring harness length for a clean replacement on the listed vehicles.

Key Features

• Heated oxygen sensor for faster operating readiness
• Specific fit design for direct replacement on listed applications
• 4-wire configuration with 15.7500-inch harness length
• 18.000 thread diameter with threaded mounting type
• Built by NTK, the Sensor Specialist and a major OE oxygen sensor supplier

Product Details

As part of the NTK Direct Fit Oxygen Sensor line, part number 21513 is engineered for import and domestic emission control applications where accurate exhaust feedback is required. NTK uses ceramic manufacturing expertise and OE-focused testing to deliver sensors that match the original application requirements for fit and function. This part cross-references Bosch 13686 and Delphi ES20088 for the same application. It is listed for downstream and upstream positions across select Buick, Cadillac, Chevrolet, GMC, and Pontiac vehicles, including 2008-2009 Buick Allure and LaCrosse, 2008 Pontiac Grand Prix, and 2001-2002 Chevrolet Silverado and GMC Sierra platforms.

What It Helps Fix

• Check engine light related to oxygen sensor performance
• Incorrect air-fuel ratio readings
• Reduced fuel control caused by aging sensor response
• Emission test failures tied to sensor output issues
• Rough running conditions associated with faulty exhaust feedback

Installation Notes and Tips

• Confirm the sensor position before ordering: upstream left, upstream right, downstream left, or downstream right.
• Verify the thread diameter and harness length against the original sensor before installation.
• Use the vehicle’s OE routing path to keep the harness away from heat and moving components.
• For fitment examples, this part fits 2008-2009 Buick LaCrosse, downstream; fits 2001-2002 Chevrolet Silverado 2500 HD, upstream left; and fits 2001-2002 GMC Yukon XL 2500, downstream right.

Quality Assurance

NTK manufactures oxygen sensors with OE application coverage and extensive production testing to help ensure reliable performance that meets or exceeds original equipment specifications. The brand’s focus on ceramic sensor technology and direct-fit coverage supports consistent replacement quality for the listed applications.