NTK 21077 Oxygen Sensor - Downstream Left or Downstream Right

Direct-fit oxygen sensor

NTK 21077 is a direct-fit heated oxygen sensor built for specific applications that require threaded mounting and a 4-wire configuration. It is engineered for downstream service and is listed for Cadillac CT6, Cadillac ATS, Cadillac CTS, and Chevrolet Camaro applications.

Key features

• Direct Fit Oxygen Sensor line for specific-fit replacement
• Heated sensor design for faster operating response
• 4-wire configuration with 10.25-inch wiring harness length
• 18.000 thread diameter with threaded mounting type
• NTK 21077 is manufactured to meet or exceed OE specifications

Detailed description

NTK 21077 is part of NTK's Direct Fit Oxygen Sensor line, created for import and domestic emission control applications where exact-fit replacement matters. As an oxygen sensor for downstream use, it supports closed-loop exhaust monitoring on compatible Cadillac CT6, Cadillac ATS, Cadillac CTS, and Chevrolet Camaro models. The heated design and specific-fit construction help maintain proper sensor response and simplify replacement on the listed applications. NTK 21077 cross-references 12666671 for the same application.

What it is used for

• Replacing a worn or slow-responding downstream oxygen sensor
• Addressing oxygen sensor fault codes related to exhaust monitoring
• Restoring proper air-fuel feedback on listed applications
• Correcting drivability issues tied to inaccurate exhaust readings
• Servicing a threaded, direct-fit sensor location with OE-style dimensions

Installation notes and tips

Verify the downstream left or downstream right position before ordering, since fitment varies by application. Confirm the 4-wire connector style, threaded mounting, and harness length against the original sensor. Use the vehicle-specific fitment listing for Cadillac CT6, Cadillac ATS, Cadillac CTS, and Chevrolet Camaro applications to match the correct location. NTK 21077 is a specific-fit replacement, so no universal adaptation should be assumed.

Quality assurance

NTK is part of the NGK family of products and is a major original equipment oxygen sensor supplier. Each sensor is extensively tested during manufacturing to support quality and reliability that meet or exceed OE specifications. Part number 21077 is backed by NTK's OE-focused manufacturing approach.