O2 Oxygen Sensor Upstream Downstream for Acura TSX (2009-2014) 2.4L

Direct-Fit O2 Oxygen Sensor Kit for 2009-2014 Acura TSX (CU2)

What it Does: The Upstream and Downstream Oxygen Sensor Kit restores accurate closed-loop air-fuel metering and emissions monitoring on the 2009-2014 Acura TSX to eliminate diagnostic trouble codes and optimize combustion efficiency.

The Stock Acura TSX Sensor Degradation

Factory lambda sensors on the high-revving K24Z3 engine suffer from thermal fatigue, silicone contamination, and soot accumulation over time. Prolonged exposure to 1,400°F exhaust gas temperatures degrades the internal zirconium dioxide ceramic element and internal heater circuits. This wear leads to sluggish switching response, false lean readings, unmetered rich fuel trims, fouled spark plugs, failed emissions tests, and recurring check engine lights such as P0134, P0135, or P0420.

The Engineering Solution

This 2-piece sensor set provides matched factory-spec monitoring for both pre-catalyst wideband air-fuel ratio metering and post-catalyst emissions verification. Constructed with double-layer 310 stainless steel shielding, high-grade planar ceramic sensing elements, and integrated fast-acting ceramic heaters, these sensors deliver rapid light-off and precise voltage feedback to the ECU. Pre-crimped OE-style weatherproof wiring harnesses with factory-correct pinouts and high-temperature PTFE insulation ensure true plug-and-play installation without wire splicing.

What's Included

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

Technical Specifications

Compatibility

• 2009-2014 Acura TSX Base Sedan 2.4L 4-Cylinder
• 2011-2014 Acura TSX Sport Wagon 2.4L 4-Cylinder

Frequently Asked Questions & Fitment Warnings

Does this fit the CU2 TSX?

Yes, this is a direct fit for the 2009-2014 Acura TSX equipped with the K24Z3 2.4L 4-cylinder engine; it does not fit 3.5L V6 (J35Z6) models.

Should anti-seize compound be used during installation?

Use high-temperature anti-seize exclusively on the sensor threads while taking strict care not to contaminate the exposed ceramic sensor tip.

The Acura Caliber

Engineered to handle high-rpm Honda i-VTEC exhaust dynamics, this matched O2 sensor set maintains precise stoichiometric control to deliver crisp throttle response and clean tailpipe emissions.