O2 Oxygen Sensor Upstream Downstream for Honda Accord (2003-2007) 2.4L

Direct-Fit Replacement Oxygen Sensor Kit for 2003-2007 Honda Accord (CM5/CM7)

What it Does: The Upstream and Downstream Oxygen Sensor Kit replaces degraded factory exhaust gas sensors on the 2003-2007 Accord 2.4L to restore closed-loop air-fuel metering, eliminate diagnostic trouble codes, and recover lost fuel economy.

The Stock Honda Accord Sensor Degradation

Over extended operating cycles, factory zirconia sensors on the Honda Accord CM5/CM7 succumb to thermal fatigue, exhaust soot contamination, and heater circuit burnout. High exhaust gas temperatures (EGT) and blow-by oil vapors coat the porous ceramic sensing element, creating sluggish switching response times. This latency degrades the engine control module's (ECM) ability to calculate precise short-term fuel trim (STFT), resulting in rich-running conditions, unburned hydrocarbon emissions, catalytic converter degradation, and recurring fault codes such as P0134, P0135, or catalyst efficiency codes like P0420.

The Engineering Solution

Engineered to match OEM switching rates, this dual-sensor set restores factory stoichiometric calculation precision (14.7:1 AFR). Each sensor features a fast-acting integrated planar ceramic heating element that accelerates closed-loop readiness during cold starts, dramatically reducing cold-cycle emissions. Designed as direct drop-in replacements for 36531-RAA-A01 (upstream air/fuel ratio) and 36532-RAA-A01 (downstream monitoring), these sensors incorporate OE-grade weather-pack terminal connectors, high-temperature silicone-jacketed lead wires, and laser-welded stainless steel bodies to prevent moisture ingress and signal degradation on your K24A powertrain.

What's Included

• 1x Upstream Oxygen (Air/Fuel Ratio) Sensor
• 1x Downstream Oxygen Sensor

Technical Specifications

Compatibility

• 2003-2007 Honda Accord DX 2.4L 4-Cylinder
• 2003-2007 Honda Accord EX 2.4L 4-Cylinder
• 2003-2007 Honda Accord LX 2.4L 4-Cylinder
• 2006-2007 Honda Accord Special Edition 2.4L 4-Cylinder
• 2006-2007 Honda Accord Value Package 2.4L 4-Cylinder

Frequently Asked Questions & Fitment Warnings

Does this fit the CM5/CM7 Accord?

Yes, this is a direct fit for the 2003-2007 Honda Accord equipped with the K24A4 or K24A8 2.4L engine. This kit does not fit 3.0L V6 (J30A4/J30A5) or Hybrid models.

Do I need to reset the ECM after installing these sensors?

Yes, clear all diagnostic trouble codes using an OBD-II scanner and execute a complete drive cycle so the engine control module can relearn base fuel trim values.

The Honda Calibration Standard

Honda's K-series platform relies on rapid, pinpoint AFR feedback to balance high-revving VTEC efficiency with low-rpm fuel economy. Installing a matched upstream and downstream sensor set ensures consistent voltage delivery, restoring crisp throttle response and factory-grade engine performance.