NTK 25191 Oxygen Sensor - Upstream

Direct Fit Oxygen Sensor for Suzuki Verona

NTK Oxygen Sensor 25191 is a direct fit, heated oxygen sensor built for specific applications on the 2006 Suzuki Verona. It is engineered for upstream placement and OE-style signal accuracy, making it a practical replacement when the original sensor is worn, slow to respond, or triggering emissions-related faults.

As part of NTK’s Direct Fit Oxygen Sensor line, this sensor is built around exact application coverage and OE-style fit, form, and function. NTK is a long-standing original equipment oxygen sensor supplier, and this part reflects that focus on ceramic sensor control, manufacturing consistency, and application-specific coverage.

Key Features

• NTK part number 25191 direct fit oxygen sensor
• Heated sensor design for faster operating temperature
• Specific fit for the listed Suzuki Verona applications
• 4-wire configuration with threaded mounting
• 18 mm thread diameter and 15.75 in. wiring harness length
• Upstream placement for Bank 1 Sensor 1 and Bank 2 Sensor 1 applications

Fitment Details

Compatible with 2006 Suzuki Verona, upstream, cylinders 1-3, Bank 1 Sensor 1. Compatible with 2006 Suzuki Verona, upstream, cylinders 4-6, Bank 2 Sensor 1. If you are searching for a 2006 Suzuki Verona upstream oxygen sensor or an OE-style replacement for NTK 25191, this part matches the listed applications exactly.

What This Sensor Helps Address

• Check engine light caused by oxygen sensor performance faults
• Slow or inaccurate air-fuel ratio feedback
• Emissions test failures related to upstream sensor readings
• Rough idle or drivability issues tied to sensor degradation
• Fuel trim problems caused by a failing heated O2 sensor

Installation Notes and Tips

Verify the connector, wire count, thread size, and upstream bank/sensor location before installation. This NTK 25191 oxygen sensor uses a threaded mount and a 4-wire heated design, so matching the original harness routing and sensor position is important for proper installation. Confirm whether your vehicle requires Bank 1 Sensor 1 or Bank 2 Sensor 1 before ordering.

Quality Assurance

NTK manufactures oxygen sensors with OE-level application coverage and extensive testing during production to support fit, function, and reliability. The brand’s OE supplier background and ceramic sensor expertise are central to the design of this direct fit replacement for the Suzuki Verona.