O2 Oxygen Sensor Upstream Downstream for Buick Enclave (2012-2017) 3.6L

Direct-Fit Oxygen Sensor Kit for 2012-2017 Buick Enclave (Lambda)

What it Does: The 4-piece direct-fit oxygen sensor kit monitors exhaust gas stoichiometry on the 2012-2017 Buick Enclave to restore closed-loop fuel trim accuracy and resolve emissions-related check engine lights.

The Stock Buick Enclave Sensor Degradation

Over extended heat cycling and high mileage, factory zirconia sensors on the 3.6L LLT direct-injection engine develop carbon fouling and internal ceramic element degradation. As heater circuits fail and sensor response times slow, the ECM defaults to sub-optimal open-loop fueling maps. This condition causes sluggish throttle response, elevated fuel consumption, tailpipe odor, and recurring diagnostic trouble codes such as P0135, P0155, P0420, and P0430 across the Lambda platform.

The Engineering Solution

Engineered to match factory switching profiles, this matched upstream and downstream set utilizes high-density ceramic sensing elements with fast-acting internal heaters. Precision laser-welded stainless steel bodies resist thermal shock and road-grime intrusion. Each sensor features direct-plug harness connectors and high-temperature lead sleeving to directly replace OEM numbers 12640453, 12590035, and 234-4566 without wire cutting, soldering, or pin repinning.

What's Included

• 2x Upstream Oxygen Sensors (Bank 1 & Bank 2 Sensor 1)
• 2x Downstream Oxygen Sensors (Bank 1 & Bank 2 Sensor 2)

Technical Specifications

Compatibility

• 2012 Buick Enclave 3.6L V6
• 2013 Buick Enclave 3.6L V6
• 2014 Buick Enclave 3.6L V6
• 2015 Buick Enclave 3.6L V6
• 2016 Buick Enclave 3.6L V6
• 2017 Buick Enclave 3.6L V6

Frequently Asked Questions & Fitment Warnings

Does this fit the Lambda Enclave?

Yes, this is a direct fit for the 2012-2017 Buick Enclave equipped with the 3.6L LLT engine.

Do these sensors require wire splicing or universal connectors?

No, these sensors feature factory-style direct-fit connectors for plug-and-play installation without wire splicing.

The Buick Reliability Standard

Full-size Buick crossover platforms demand precise closed-loop fueling management to preserve catalytic converter core integrity and sustain factory efficiency over heavy daily commuting.