GUZIKO O2 Oxygen Sensor for Honda TRX420/TRX500 Rancher Foreman Rubicon — Direct Fit, OE Replacement

GUZIKO O2 Oxygen Sensor is a direct-fit replacement oxygen sensor engineered to restore accurate exhaust oxygen readings for Honda TRX420 and TRX500 Rancher, Foreman and Rubicon models, matching OE part numbers 36531-HR3-A22 and 36531-HR3-A21.

This GUZIKO sensor is built to the fit and function expectations of Honda utility ATVs from the mid-2010s. It connects into the original wiring harness and provides the exhaust oxygen data the engine control unit (ECU) needs to regulate air‑fuel ratio. The unit is constructed from durable materials to withstand heat and vibration typical of off-road riding, and it’s backed by a 12‑month after‑sale service commitment.

Which Honda models and years will this sensor fit?

The GUZIKO O2 sensor is designed as a direct replacement for specific Honda TRX models. Check your vehicle’s year and model against the listed compatibility before ordering to be certain of fitment.

• Honda TRX420 Rancher: 2014, 2015, 2016, 2017, 2018, 2019
• Honda TRX500 Rancher: 2015, 2016
• Honda TRX500 Foreman: 2015, 2016, 2017, 2018, 2019
• Honda TRX500 Rubicon: 2015, 2016, 2017, 2018, 2019

How does this replacement sensor help engine operation?

The oxygen sensor measures exhaust oxygen content and relays signals to the ECU, which adjusts fuel delivery to maintain the intended air‑fuel mixture. A functional sensor helps the engine run more consistently and reduces symptoms caused by incorrect mixture readings.

• Provides real‑time oxygen measurements to the ECU
• Supports stable acceleration and smoother idling
• Helps reduce fuel trim errors caused by a failing sensor

Is this an OEM part and what numbers does it replace?

GUZIKO supplies this sensor as a high-quality aftermarket replacement that matches the specifications of the original equipment part numbers listed by Honda. Verify your current part number to ensure compatibility before installation.

• Replaces OE part numbers: 36531-HR3-A22 and 36531-HR3-A21
• Form, connector and thread size designed to match factory mount points
• Undergone quality inspection before shipping

What should I know about installation and after-sales support?

Installation instructions are not included; professional inspection and installation are strongly recommended to ensure correct wiring and sealing. GUZIKO offers a 12‑month after‑sale service—contact customer support if you run into fitment or performance concerns and expect a response within 12 hours.

• No installation manual supplied—seek professional installation
• 12 months of after‑sale coverage for defects or questions
• Customer service response typically within 12 hours

Who is this for: This GUZIKO O2 Oxygen Sensor is intended for Honda TRX420 and TRX500 owners who need a reliable, direct-fit replacement for a worn or faulty oxygen sensor. It’s appropriate for riders and technicians who expect OE-equivalent fitment for model years listed above and who will have the part professionally installed and inspected. Confirm your ATV’s model year and the current part number before purchase to ensure proper compatibility.