Denso 234-4376 Oxygen Sensor - Downstream
OE Quality 60-Day Returns
Denso
 OE Style

Denso 234-4376 Oxygen Sensor - Downstream

Brand Denso 234-4376
Position Downstream
Wiring Harness Length 25.98
Sensor Type Heated
Universal Or Specific Fit Specific
Wire Quantity 4
Connector Gender Male
Thread Diameter 0.708
Mounting Type Threaded
Product line OE Style
Fits Mazda · 1 vehicle

OE Style fit. Built for exact replacement and first-time installation.

Heated sensor design. Supports faster operating response after startup.

Trap layer protection. Helps shield the ceramic element from contamination.

Cross-references Bosch 13621, Mazda L36318861A and NTK 24678 for the same application. See all 5.

$87.18Free shipping
In stock · usually ships same day before 1pm CST
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Order total $87.18
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Free returns within 60 days if it doesn't fit when fitment is verified.
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OE Style Oxygen Sensor

This Denso oxygen sensor is a specific-fit replacement built to OE standards for accurate installation and dependable operation. It is a heated, threaded sensor with a 4-wire male connector and a 25.98-inch harness for a direct replacement on the listed application.

Key Features

  • OE Style line for exact replacement fit and first-time installation
  • Heated oxygen sensor design for faster operating response
  • Exclusive aluminum oxide trap layer helps protect the sensing element from silicone and lead contamination
  • 4-wire configuration with male connector
  • Threaded mounting type with 0.708-inch thread diameter

Detailed Description

Denso 234-4376 is an OE-style oxygen sensor engineered for the listed Mazda 6 downstream application. Built and tested to OE standards, this sensor is made for precise replacement fitment and consistent signal performance. The aluminum oxide trap layer adds protection for the ceramic element, helping preserve sensor function and supporting fuel efficiency and engine performance over time. If you need a Mazda 6 oxygen sensor replacement, Denso 234-4376 provides the correct fit and configuration for the specified California emissions application.

This part cross-references Bosch 13621 and NTK 24678 for the same application.

What It Helps Solve

  • Check engine light caused by a failing downstream oxygen sensor
  • Incorrect air-fuel feedback from a worn sensor element
  • Reduced fuel economy related to poor exhaust oxygen readings
  • Slow sensor response after contamination or age-related wear
  • Fitment issues from using the wrong connector or thread style

Installation Notes and Tips

Fits 2005 Mazda 6, downstream. Verify California emissions configuration, downstream location after the primary catalyst, connector style, wire count, and thread size before installation. Use the listed application data to confirm the correct Mazda 6 oxygen sensor replacement and avoid fitment errors.

Quality Assurance

Denso manufactures and tests this sensor to strict OE standards for exact replacement fitment and consistent performance.

Related reading

This part fits 1 vehicle
Always verify fitment with your vehicle's VIN if unsure. Submodel & trim restrictions may apply.
YearMakeModelTransmissionPositionNotes
2005Mazda6AutomaticDownstreamLoc. After Primary Catalyst; Calif.; OE Style
Directly replaces or cross-references 5 part numbers
Cross-reference numbers are provided for identification purposes only. Always confirm fitment before ordering.
Bosch — 13621Mazda — L36318861ANTK — 24678Walker Products — 250-24424Walker Products — 350-34140