Denso O2 Oxygen Sensor 234-4621 — Direct-Fit for Select Acura & Honda, 4-Wire Heated Zirconia

This replacement O2 sensor from Denso is engineered to match original equipment fit and function for a range of Acura and Honda vehicles. It uses a refined zirconia sensing element and Denso's protective aluminum oxide trap layer to resist common contaminants, while a 4-wire 20.28-inch harness simplifies installation and electrical integration. The result is a component designed to deliver dependable readings, corrosion resistance, and a long service life when compared to cheaper aftermarket alternatives.

How will this sensor affect my vehicle’s performance?

Accurate oxygen readings are essential for the engine control unit to maintain the correct air–fuel ratio. Installing a properly functioning sensor helps the ECU make precise fuel trims, which supports smoother idling, consistent throttle response, and more stable emissions control.

• Refined zirconia element gives faster, reliable voltage response to exhaust oxygen content.
• PTFE filter reduces contaminant buildup that dulls sensor accuracy.
• 4-wire harness provides heater feedback for quicker warm-up and stable readings.

Will this Denso part fit my Acura or Honda model?

Denso part 234-4621 is designed for a specific list of Acura and Honda years and models. Confirm compatibility by cross-referencing the part number and vehicle year — the sensor is intended as a direct replacement for the listed applications and common OEM interchange numbers.

• Acura: 2001–2003 CL, 2001–2003 EL, 2000–2005 NSX, 1999–2003 TL.
• Honda: 1990–1993 & 1998–2002 Accord, 2001–2003 Civic, 1997–2001 Prelude.
• Also matches multiple OEM interchange numbers for straightforward replacement.

How is this Denso sensor protected against contamination and corrosion?

Denso adds material and design features to limit performance loss from exposure to exhaust contaminants and road conditions. Corrosion-resistant stainless steel and a PTFE filter reduce external and internal fouling, while an aluminum oxide trap protects the ceramic sensing element from silicon and lead contamination.

• Stainless steel housing resists corrosion from moisture and road salts.
• PTFE filter blocks particulates that can impair sensor response.
• Aluminum oxide trap extends element life against contaminant poisoning.

How straightforward is installation and what are the physical specs?

The sensor ships with a 4-wire 20.28-inch wiring harness to match original electrical connections and heater control. Dimensionally compact and lightweight, it’s intended for a first-time fit in compatible exhaust locations; basic mechanical skills and common tools are typically all that’s required to install it.

• Includes 20.28-inch 4-wire harness for plug-and-play electrical connection.
• Item dimensions approximately 5.75 x 2.19 x 1.88 inches; weight about 0.25 lb.
• Package quantity: 1 sensor — replace one upstream or downstream unit as needed.

Who is this for: This Denso 234-4621 O2 sensor is aimed at owners, mechanics, and restoration enthusiasts working on the listed Acura and Honda models who want an OE-quality replacement. It’s suitable for anyone seeking a robust, contamination-resistant narrow-band sensor with direct-fit wiring, including those servicing emissions systems, tuning fuel trims, or restoring vehicle drivability after a failing oxygen sensor.