O2 Oxygen Sensor Upstream Downstream for Honda Pilot Ridgeline (2009-2011) 3.5L

Direct-Fit Upstream & Downstream O2 Oxygen Sensor Kit for 2009-2011 Honda Pilot & Ridgeline (YF3/YF4, YK1)

What it Does: This 4-piece oxygen sensor kit monitors pre- and post-catalytic exhaust oxygen content on 2009-2011 Honda Pilot (YF3/YF4) and Ridgeline (YK1) 3.5L V6 engines to regulate closed-loop fuel trim and catalyst efficiency.

The Stock Honda Pilot & Ridgeline Oxygen Sensor Failure

Factory upstream air-fuel ratio sensors and downstream heated O2 sensors on the YF3/YF4 Pilot (J35Z4) and YK1 Ridgeline (J35A9) endure extreme thermal cycling and exhaust contamination. Over high mileage, internal planar heater elements burn out while zirconia ceramic substrates suffer silicone, carbon, and oil-ash fouling. This degradation causes sluggish voltage switching, open-loop fuel enrichment, and recurring P0134, P0135, P0141, P0154, or P0420/P0430 diagnostic trouble codes.

Common Symptoms of a Failing OEM Oxygen Sensor

• Check Engine Light & Heater Faults: Triggers P0135, P0141, P0155, or P0161 when internal heater circuit resistance exceeds PCM thresholds.
• Delayed Closed-Loop Transition: Sluggish P0133/P0153 response causes rich fuel trims, rough idling, and throttle hesitation.
• Failed Emissions & Fuel Economy Drop: Inaccurate downstream monitoring sets P0420/P0430 codes and reduces fuel mileage.

The Direct-Fit Zirconia Planar O2 Sensor Solution

This matched 4-piece kit replaces both upstream wideband A/F sensors and both downstream heated O2 sensors, directly replacing OEM numbers 36531-R70-A01, 36532-R70-A01, and 36532-R71-L01. Each unit features a laser-welded stainless steel housing, porous PTFE breather membrane, and fast-acting planar zirconia ceramic element for rapid light-off. Exact-length insulated leads and OEM-indexed weatherproof connectors deliver true plug-and-play installation without wire splicing.

What's Included

• 2x Upstream Air-Fuel Ratio (O2) Oxygen Sensors
• 2x Downstream Heated (O2) Oxygen Sensors

Technical Specifications

Compatibility

• 2009-2011 Honda Pilot 3.5L V6 (YF3/YF4 - J35Z4)
• 2009-2011 Honda Ridgeline 3.5L V6 (YK1 - J35A9)

Frequently Asked Questions & Fitment Warnings

Does this fit the YF3/YF4 Pilot and YK1 Ridgeline?

Yes. This is a direct fit for the 2009-2011 Honda Pilot (YF3/YF4) and Ridgeline (YK1) equipped with the J35Z4 or J35A9 3.5L V6 engine. Confirm your 3.5L engine displacement and match connector shapes before ordering; does not fit 2012+ models or non-3.5L applications.

Will replacing all four sensors clear P0135, P0141, or P0420 codes?

Yes, when sensor degradation is the root cause. Installing fresh 36531-R70-A01 upstream and 36532-R70-A01 downstream units resolves heater circuit (P0135/P0141) and slow-response faults, though persistent P0420/P0430 codes after replacement indicate failed catalytic converter substrates.

Is wire splicing or extra thread compound required for installation?

No splicing is required. All four sensors include factory-style harnesses and pre-applied thread anti-seize; torque each sensor to 33 lb-ft (44 Nm) into a cool exhaust bung using a 22mm O2 sensor socket.

The Honda Precision Standard

Accurate closed-loop fuel metering keeps the J35 V6 operating cleanly, efficiently, and free of check engine lights under daily commuting or towing loads. Replacing all four oxygen sensors as a matched set restores balanced bank-to-bank air-fuel control.