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NTK 24664 Air / Fuel Ratio Sensor - Upstream
Overview of NTK Direct Fit 4-Wire A/F Sensor 24664
The NTK Direct Fit 4-Wire A/F Sensor 24664 is designed to provide precise air/fuel ratio measurements for specific vehicle applications. This heated sensor ensures accurate emissions control and optimal engine performance for select Acura, Honda, and Subaru models.
- Heated sensor type for faster response times
- 22.0-inch wiring harness length for direct fit installation
- Specific fit for Acura, Honda, and Subaru vehicles
- 4-wire configuration for reliable signal transmission
- Thread diameter of 18.0 mm and thread length of 0.38 inches
- No mounting bracket included
Detailed Product Description
The NTK Direct Fit 4-Wire A/F Sensor 24664 is engineered to meet the exact specifications required by certain Acura, Honda, and Subaru models, including the Baja, Civic, EL, Forester, Impreza, Legacy, and Outback. This air/fuel ratio sensor features a heated element that allows it to reach operating temperature quickly, improving sensor response and reducing emissions during cold starts. The 22-inch wiring harness length provides sufficient reach for direct fit installation without the need for extensions or modifications. With a thread diameter of 18 mm and a thread length of 0.38 inches, this sensor installs securely into the exhaust system. The 4-wire design supports accurate signal output for the vehicle’s engine control unit (ECU).
About the Direct Fit 4-Wire A/F Sensor Product Line
The Direct Fit 4-Wire A/F Sensor line from NTK is tailored for specific vehicle applications, ensuring compatibility and ease of installation. These sensors are designed with a heated element and a 4-wire configuration to provide reliable air/fuel ratio readings that help maintain emissions compliance and engine efficiency. The direct fit design minimizes installation time and reduces the risk of wiring or fitment issues.
Common Applications and Issues Addressed
- Restores accurate air/fuel ratio readings for proper engine management
- Helps resolve check engine light codes related to oxygen sensor faults
- Improves fuel efficiency by providing precise sensor data
- Reduces emissions by ensuring correct combustion mixture
- Prevents drivability issues caused by faulty air/fuel sensors
Installation Notes and Tips
- Compatible with specific Acura, Honda, and Subaru models listed in fitment
- Ensure the sensor thread diameter and length match the vehicle’s exhaust port
- Do not use a mounting bracket as this sensor does not include one
- Handle the wiring harness carefully to avoid damage during installation
- Verify sensor connector compatibility before installation
Quality Assurance and Warranty
NTK air/fuel ratio sensors are manufactured to meet OEM standards for durability and performance. The Direct Fit 4-Wire A/F Sensor 24664 undergoes rigorous testing to ensure reliable operation under various driving conditions. Warranty coverage details should be confirmed with the original equipment manufacturer or authorized distributor.
| Brand | NTK |
|---|---|
| Part Number | 24664 |
| Position | Direct Fit 4-Wire A/F Sensor, Upstream |
| Mounting Bracket Included | No |
| Sensor Type | Heated |
| Thread Diameter | 18.000 |
| Thread Length | 0.38 |
| Universal Or Specific Fit | Specific |
| Wire Quantity | 4 |
| Wiring Harness Length | 22.0 |
This part fits 16 vehicles. Search below:
| Year | Make | Model | Liters | Cylinders | Position | Notes |
|---|---|---|---|---|---|---|
| 2006 | Subaru | Baja | 2.5L | H4 | Upstream | OE design oxygen sensor fits Bank 1 Sensor 1 for air/fuel ratio.; Direct Fit 4-Wire A/F Sensor |
| 2005 | Acura | EL | 1.7L | L4 | Upstream | OE design oxygen sensor fits Bank 1 Sensor 1 for air/fuel ratio.; Direct Fit 4-Wire A/F Sensor |
| 2005 | Honda | Civic | 1.7L | L4 | Upstream | OE design oxygen sensor fits Bank 1 Sensor 1 for air/fuel ratio.; Direct Fit 4-Wire A/F Sensor |
| 2005 | Subaru | Baja | 2.5L | H4 | Upstream | OE design oxygen sensor fits Bank 1 Sensor 1 for air/fuel ratio.; Direct Fit 4-Wire A/F Sensor |
| 2004 | Acura | EL | 1.7L | L4 | Upstream | OE design oxygen sensor fits Bank 1 Sensor 1 for air/fuel ratio.; Direct Fit 4-Wire A/F Sensor |
| 2004 | Honda | Civic | 1.7L | L4 | Upstream | OE design oxygen sensor fits Bank 1 Sensor 1 for air/fuel ratio.; Direct Fit 4-Wire A/F Sensor |
| 2004 | Subaru | Baja | 2.5L | H4 | Upstream | OE design oxygen sensor fits Bank 1 Sensor 1 for air/fuel ratio.; Direct Fit 4-Wire A/F Sensor |
| 2004 | Subaru | Forester | 2.5L | H4 | Upstream | OE design oxygen sensor fits Bank 1 Sensor 1 for air/fuel ratio.; Direct Fit 4-Wire A/F Sensor |
| 2004 | Subaru | Impreza | 2.5L | H4 | Upstream | OE design oxygen sensor fits Bank 1 Sensor 1 for air/fuel ratio.; Direct Fit 4-Wire A/F Sensor |
| 2004 | Subaru | Legacy | 2.5L | H4 | Upstream | B1S1 Oxygen Sensor for Federal Emissions with OE Equivalent Design; Direct Fit 4-Wire A/F Sensor |
| 2004 | Subaru | Outback | 2.5L | H4 | Upstream | B1S1 Oxygen Sensor for Federal Emissions with OE Equivalent Design; Direct Fit 4-Wire A/F Sensor |
| 2003 | Subaru | Baja | 2.5L | H4 | Upstream | OE design oxygen sensor fits Bank 1 Sensor 1 for air/fuel ratio.; Direct Fit 4-Wire A/F Sensor |
| 2003 | Subaru | Forester | 2.5L | H4 | Upstream | OE design oxygen sensor fits Bank 1 Sensor 1 for air/fuel ratio.; Direct Fit 4-Wire A/F Sensor |
| 2003 | Subaru | Impreza | 2.5L | H4 | Upstream | OE design oxygen sensor fits Bank 1 Sensor 1 for air/fuel ratio.; Direct Fit 4-Wire A/F Sensor |
| 2003 | Subaru | Legacy | 2.5L | H4 | Upstream | OE design oxygen sensor fits Bank 1 Sensor 1 for air/fuel ratio.; Direct Fit 4-Wire A/F Sensor |
| 2003 | Subaru | Outback | 2.5L | H4 | Upstream | OE design oxygen sensor fits Bank 1 Sensor 1 for air/fuel ratio.; Direct Fit 4-Wire A/F Sensor |
* Always verify fitment with your vehicle's VIN if unsure. Submodel & trim restrictions may apply.
This part directly replaces or is cross-referenced with the following part numbers:
Cross-reference numbers are provided for identification purposes only. Always confirm fitment before ordering.