O2 Oxygen Sensor Upstream Downstream for Hyundai Tucson (2010-2015) 2.0L 2.4L

Direct-Fit Upstream & Downstream O2 Oxygen Sensor Kit for 2010-2015 Hyundai Tucson (LM)

What it Does: This matched upstream and downstream oxygen sensor kit monitors pre- and post-catalyst exhaust gas oxygen levels on the LM chassis 2010-2015 Hyundai Tucson 2.0L and 2.4L engines to regulate closed-loop air-fuel ratios and verify catalytic converter efficiency.

The Stock Hyundai Tucson Oxygen Sensor Failure

Factory oxygen sensors on the LM Tucson equipped with the Theta II G4KD / G4KE or Nu G4NC four-cylinder engines endure extreme exhaust thermal cycles exceeding 1,400°F. Over time, oil ash, fuel additives, and moisture contaminate the porous ceramic zirconia element, causing sluggish voltage switching and internal heater circuit burnout. Carbon fouling delays closed-loop fuel trim response, skewing ECU injector pulse-width calculations and frequently triggering P0133, P0135, and P0141 fault codes.

Common Symptoms of a Failing OEM Oxygen Sensor

• Check Engine Light / Heater & Response DTCs: Faults such as P0133 (slow response), P0135 (upstream heater circuit), or P0141 (downstream heater circuit) trigger when internal resistance spikes or sensor switching lags.
• Fuel Trim Drift & Rough Idle: Sluggish upstream feedback forces inaccurate fuel trim compensation, causing hesitation under load, sulfur exhaust odor, and P0171 or P0172 codes.
• Increased Fuel Consumption & Emissions Failure: Prolonged open-loop fueling wastes fuel, overheats the catalytic substrate, and prevents OBD-II readiness monitors from setting.

The Direct-Fit Dual-Sensor Oxygen Sensor Solution

Replacing both units as a matched pair restores synchronized pre- and post-catalyst signal feedback across the LM exhaust manifold and mid-pipe. Each direct-fit sensor utilizes a stainless steel protective shield, high-temperature ceramic sensing element, and factory-calibrated internal heater coil for rapid cold-start light-off. Pre-terminated OEM-style weatherproof connectors and exact-length harness leads eliminate wire splicing, directly replacing interchange numbers 234-5029 and 234-4238 with factory thread pitch and sealing geometry.

What's Included

• 1 Upstream Oxygen Sensor
• 1 Downstream Oxygen Sensor

Technical Specifications

Compatibility

• 2010-2013 Hyundai Tucson 2.4L (California Emissions)
• 2014-2015 Hyundai Tucson 2.4L
• 2011-2013 Hyundai Tucson 2.0L (Automatic Transmission, California Emissions)
• 2014 Hyundai Tucson 2.0L

Frequently Asked Questions & Fitment Warnings

Does this fit the LM Tucson?

Yes. This is a direct fit for the 2010-2015 Hyundai Tucson equipped with the 2.0L or 2.4L (G4KD / G4KE / G4NC) engine. Confirm engine, transmission, and emissions spec before ordering: 2010-2013 2.4L models require California emissions, 2011-2013 2.0L models require automatic transmission with California emissions, and 2015 2.0L, Santa Fe, Sonata, and Kia applications are excluded.

Will this kit clear P0135, P0141, or P0420 codes?

Yes for sensor faults; conditional for P0420. Installing fresh sensors directly resolves slow-response and heater circuit codes such as P0133, P0135, and P0141, while a P0420 code will only clear if the downstream sensor was falsely reporting catalyst inefficiency rather than a damaged catalytic converter core.

Is any wiring modification required during installation?

No wiring modification is required. Both sensors arrive with OEM-style plug-and-play connectors replacing 234-5029 and 234-4238; thread into the factory exhaust bungs using a 22mm O2 sensor socket and apply anti-seize only to the threads while keeping the sensing tip clean.

The Hyundai Precision Standard

Accurate closed-loop air-fuel monitoring is essential for protecting the catalytic converter and maintaining strict emissions compliance on your LM Hyundai Tucson. Replacing worn upstream and downstream sensors as a matched pair restores stable ECU fuel trim control and reliable, CEL-free operation.