NTK 24664 Air / Fuel Ratio Sensor - Upstream

Direct-Fit Air/Fuel Ratio Sensor

NTK 24664 is a direct-fit heated air/fuel ratio sensor built for specific upstream applications. It is engineered for OE-style fit, form, and function, with a 4-wire design and a 22.0 in. wiring harness for clean replacement on select Subaru, Honda, and Acura vehicles.

Compatible With 2003-2006 Subaru Baja, 2004-2005 Honda Civic, and 2004-2005 Acura EL upstream Bank 1 Sensor 1 applications, this NTK sensor supports accurate air/fuel monitoring in the exhaust stream. The NTK Direct Fit 4-Wire A/F Sensor line focuses on application-specific replacement parts for import and domestic vehicles, including OE-equivalent coverage for select Subaru Legacy and Outback Federal Emissions applications.

Key Features

• NTK part number 24664
• Direct Fit 4-Wire A/F Sensor for specific applications
• Heated sensor design for faster operating response
• 22.0 in. wiring harness length
• 18.000 mm thread diameter with 0.38 thread length
• Specific fit replacement for upstream Bank 1 Sensor 1 locations
• No mounting bracket included

Application Details

NTK is known for oxygen and air/fuel ratio sensor manufacturing, with ceramic-based production control and extensive testing during manufacturing. That process supports consistent fit and signal performance for OE-style replacement needs. Part number 24664 is listed for select 2003-2006 Subaru Baja, 2003-2004 Subaru Forester, 2003-2004 Subaru Impreza, 2003-2004 Subaru Legacy, 2003-2004 Subaru Outback, 2004-2005 Honda Civic, and 2004-2005 Acura EL upstream positions. This part cross-references Bosch 15473 for the same application.

What It Helps Address

• Check engine light related to upstream air/fuel sensor performance
• Rough idle caused by incorrect air/fuel feedback
• Fuel trim issues from a slow or inaccurate sensor signal
• Emissions test failures tied to sensor response problems
• Driveability concerns on Bank 1 Sensor 1 applications

Installation Notes

Verify the vehicle’s year, make, model, and upstream Bank 1 Sensor 1 location before ordering. Confirm connector style, harness routing, and thread specifications against the original sensor. Because this is a specific-fit replacement, it should be matched to the exact application listed for Subaru, Honda Civic, and Acura EL vehicles.

Quality Assurance

NTK manufactures oxygen and air/fuel ratio sensors with OE-focused engineering and manufacturing controls. Each sensor is extensively tested during production to help meet or exceed OE specifications for fit and reliability.