NTK
Direct Fit Oxygen Sensor

NTK 22101 Oxygen Sensor - Downstream

Brand NTK 22101
Position Downstream
Mounting Type Threaded
Sensor Type Heated
Thread Diameter 18.000
Universal Or Specific Fit Specific
Wire Quantity 4
Wiring Harness Length 24.0000
Product line Direct Fit Oxygen Sensor
Fits Mazda · 4 vehicles

Direct fit replacement. Specific-fit oxygen sensor for straightforward installation.

Heated sensor. Helps the sensor reach operating temperature quickly.

Threaded mounting. Installs with a secure, threaded connection.

Cross-references Bosch 15426, DENSO Auto Parts 234-4393 and 75-2643 for the same application. See all 6.

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Direct Fit Oxygen Sensor for Mazda 6

NTK 22101 is a direct fit heated oxygen sensor built for specific downstream applications on the Mazda 6. It uses a 4-wire, threaded design with a 24-inch wiring harness and an 18 mm thread diameter for OE-style replacement on the correct bank and sensor location.

As part of NTK’s Direct Fit Oxygen Sensor line, this sensor is built around OE application coverage and precise fitment for import and domestic vehicles. For 2003-2005 Mazda 6 downstream service, NTK 22101 supports the original sensor layout without requiring a universal adaptation.

Key Features

  • Direct fit oxygen sensor for specific downstream applications
  • Heated sensor design for faster operating response
  • 4-wire configuration with 24-inch wiring harness
  • Threaded mounting with 18 mm thread diameter
  • OE-style fit, form, and function for Mazda 6 service
  • Cross-reference: Bosch 15426; DENSO Auto Parts 234-4393

Detailed Description

NTK 22101 is an emission control oxygen sensor engineered for downstream use on the Mazda 6. It is listed for 2005 Mazda 6 downstream B1S2 applications with California emissions and federal emissions, and for 2003-2004 Mazda 6 downstream B1S2 applications that meet OEM standards. This part number is also identified as a direct fit oxygen sensor for the same application family.

NTK’s Direct Fit Oxygen Sensor line focuses on OE application coverage and controlled ceramic manufacturing, helping maintain consistent sensor performance from raw material through finished product. NTK is a major original equipment oxygen sensor supplier, and this part reflects that OE-oriented approach for Mazda 6 oxygen sensor replacement.

Common Issues This Sensor Can Address

  • Check engine light related to downstream oxygen sensor performance
  • Fault codes tied to B1S2 sensor readings
  • Slow or inaccurate oxygen sensor response
  • Emission control failures caused by a worn heated sensor
  • Replacement needs for a damaged or aging threaded sensor assembly

Installation Notes and Tips

Confirm the vehicle year, emissions package, and downstream B1S2 location before ordering. This sensor uses a threaded mounting style and a specific-fit harness, so match the connector routing and sensor position to the original unit on the Mazda 6. Verify the 4-wire layout and 24-inch harness length against the existing sensor before installation.

Quality Assurance

NTK tests oxygen sensors during manufacturing to support quality and reliability that meet or exceed OE specifications. The Direct Fit Oxygen Sensor line is built for OE application technology and consistent fitment on the intended Mazda 6 downstream applications.

This part fits 4 vehicles
Always verify fitment with your vehicle's VIN if unsure. Submodel & trim restrictions may apply.
YearMakeModelTransmissionLitersCylindersPositionNotes
2005Mazda6Manual2.3LL4DownstreamB1S2; Calif. Emissions; OE MFR: NTK; Direct Fit Oxygen Sensor
2005Mazda6—2.3LL4DownstreamB1S2; Federal Emissions; OE MFR: NTK; Direct Fit Oxygen Sensor
2004Mazda6—2.3LL4DownstreamB1S2 oxygen sensor meets OEM standards.; Direct Fit Oxygen Sensor
2003Mazda6—2.3LL4DownstreamB1S2 oxygen sensor meets OEM standards.; Direct Fit Oxygen Sensor
Directly replaces or cross-references 6 part numbers
Cross-reference numbers are provided for identification purposes only. Always confirm fitment before ordering.
Bosch — 15426DENSO Auto Parts — 234-439375-2643L33418861BOS2097SG1211