GM GENUINE PARTS Heated Oxygen (O2) Sensor 12665061 — OE Fit with Integrated Heater

GM Genuine Parts 12665061 is a heated oxygen (O2) sensor engineered to monitor exhaust oxygen and help the engine control unit maintain the correct air/fuel ratio.

This GM Genuine Parts O2 sensor is built to General Motors' factory specifications to provide reliable feedback to the engine control module (ECM). By measuring the oxygen level in exhaust gases, the sensor enables the ECM to fine-tune fuel delivery for optimized combustion, emissions control, and fuel efficiency. The 12665061 version includes an integrated heater for faster warm-up and stable operation across temperature ranges; it also requires programming or special setup procedures as explained in GM Service Information.

How does this heated oxygen sensor improve engine performance?

The sensor continuously reports oxygen content in the exhaust so the ECM can adjust the air/fuel mixture toward the stoichiometric target. Faster warm-up from the internal heater reduces time the engine runs in open-loop mode, improving drivability and emissions during cold starts.

• Heated element speeds sensor response after startup
• Precise oxygen measurements enable tighter fuel control
• Helps maintain optimal combustion across operating conditions

What should I know about installation and programming?

GM specifies that some oxygen sensors, including this one, require programming or special setup to function correctly with vehicle systems. Follow GM Service Information and use the recommended tools to ensure the ECM recognizes the new sensor and that diagnostic parameters are reset where required.

• Refer to GM Service Information for calibration steps
• May need OE-level scan tools or reprogramming procedures
• Proper wiring and connector mating are essential for heater and signal operation

Will this part fit my Chevrolet, Buick, GMC, or Cadillac?

GM Genuine Parts are designed and validated by GM engineers to match the original equipment used on GM vehicles. Always verify part number compatibility with your vehicle’s year, make, model, engine code, and original part number before purchase.

• Manufactured to OE specifications for GM vehicles
• Cross-check VIN or original part number for fitment
• Some items formerly marketed under ACDelco GM Original Equipment

How does this sensor help with emissions and fuel economy?

By providing accurate oxygen readings, the sensor allows the ECM to maintain an air/fuel ratio near 14.7:1 under most conditions, which supports efficient combustion and reduces excess pollutants. Stable sensor performance helps the vehicle meet emissions standards and supports consistent fuel consumption.

• Supports closed-loop fueling for better economy
• Helps lower tailpipe emissions by preventing overly rich or lean mixtures
• Durable design meets GM testing and validation standards

Who is this for: The GM Genuine Parts 12665061 Heated Oxygen Sensor is intended for owners and technicians of GM vehicles who need a direct-fit, OE-validated O2 sensor. It suits professional installers and knowledgeable DIYers who can perform required programming or have access to GM service procedures and scan tools. Choose this part if you want a factory-spec replacement that matches GM engineering and validation standards.