NTK 25610 Oxygen Sensor - Downstream or Upstream

Direct Fit Oxygen Sensor for Kia Spectra

The NTK 25610 is a direct fit heated oxygen sensor built for specific applications on the Kia Spectra. It uses a threaded mounting design and a 4-wire configuration to match the original equipment style connection and response.

Key Features

• Specific-fit oxygen sensor for confirmed Kia Spectra applications
• Heated sensor design for faster operating readiness
• 4-wire layout for OE-style signal and heater circuit integration
• Threaded mounting type for direct installation into the exhaust stream
• 21.75-inch wiring harness length for application-specific routing
• NTK 25610 part number for accurate replacement matching

Application Details

Fits 2003-2004 Kia Spectra, upstream. Fits 2003-2004 Kia Spectra, downstream. Fits 2002 Kia Spectra, upstream. Fits 2002 Kia Spectra, downstream. Notes include Bank 1 Sensor 1, Bank 1 Sensor 2, and OE-equivalent design references for the listed applications. This part cross-references Bosch (e.g., 15643, 15644) for the same application.

What It Helps Address

• Faulty oxygen sensor readings that can trigger engine management concerns
• Slow sensor warm-up that affects closed-loop fuel control
• Exhaust feedback issues tied to worn or aging sensor elements
• Replacement needs for specific Kia Spectra upstream and downstream positions

Installation Notes and Tips

Confirm the listed year, position, and notes before ordering. The threaded design and specific-fit configuration are intended to match the original sensor location and connector routing on the applicable Kia Spectra models. Verify harness length and sensor placement against the removed unit before installation.

Quality Assurance

NTK is part of the NGK family of products and is recognized as a major original equipment oxygen sensor supplier. Each sensor is extensively tested during manufacturing to meet or exceed OE specifications for fit, form, and function. The NTK 25610 reflects that OE-focused manufacturing approach.