O2 Oxygen Sensor Upstream Downstream for Honda Accord (2008-2012) 2.4L

Direct-Fit Upstream and Downstream Oxygen Sensor Kit for 2008-2012 Honda Accord (CP2)

What it Does: The upstream and downstream oxygen sensor kit monitors exhaust gas stoichiometry and catalyst efficiency on the 2008-2012 Honda Accord to restore precise closed-loop fueling and eliminate diagnostic trouble codes.

The Stock Honda Accord Sensor Degradation

The factory zirconia elements on the 8th generation Accord degrade from continuous thermal cycling, carbon soot buildup, and silica contamination in the exhaust stream. As response times lag, the ECM struggles to maintain the stoichiometric 14.7:1 air-fuel ratio. This sluggish feedback loop results in rich-running conditions, fouled spark plugs, premature catalytic converter degradation, and recurring Check Engine lights (P0135, P0134, P0420).

The Engineering Solution

This paired replacement set includes both the wideband air-fuel ratio sensor (upstream) and the secondary heated oxygen sensor (downstream). Built with planar ceramic sensing elements and integrated rapid-light-off internal heaters, these direct-fit sensors reach operating temperature in seconds. Double-sealed stainless steel protective bodies resist thermal shock and road debris intrusion, while factory-pinned waterproof terminals plug directly into the engine harness without splicing.

What's Included

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

Technical Specifications

Compatibility

• 2008-2012 Honda Accord 2.4L (Sedan & Coupe)
• 2009-2014 Acura TSX 2.4L

Frequently Asked Questions & Fitment Warnings

Does this fit the CP2 Accord?

Yes, this is a direct fit for the 2008-2012 Honda Accord equipped with the K24Z2 / K24Z3 2.4L inline-four engine; it does not fit 3.5L V6 (J35) models.

Should anti-seize compound be applied to the threads before installation?

Yes, coat the stainless steel threads with high-temperature anti-seize lubricant, taking care not to contaminate the protective sensor snout.

The Honda Caliber

Keep your JDM four-cylinder powertrain operating at peak thermal and volumetric efficiency with accurate closed-loop signaling that protects your exhaust catalysts and restores crisp throttle dynamics.