GM NOx (Nitrogen Oxide) sensor is an automotive sensor that measures the amount of nitrogen oxide in the engine’s exhaust gas. It is a critical component of a vehicle’s emission control system, as nitrogen oxide emissions can be harmful to the environment and can contribute to smog and acid rain.

The NOx sensor works by measuring the difference in oxygen levels between the engine intake and exhaust systems. Within the sensor, there are two chambers separated by a thin ceramic membrane. The first chamber is exposed to the vehicle’s exhaust gas, while the second chamber is exposed to ambient air. When the nitrogen oxide in the exhaust reacts with the oxygen in the sensor’s second chamber, it produces an electrical signal that is sent to the engine control module (ECM).

The ECM uses this information to adjust the engine’s air-fuel ratio and timing to reduce nitrogen oxide emissions. If the NOx sensor fails or begins to malfunction, it can cause a variety of symptoms, such as reduced engine power, increased fuel consumption, and increased emissions.

GM produces a range of NOx sensors for its vehicles, and different models may use different part numbers depending on the year and make of the vehicle. It is important to use the correct part number for your specific vehicle to ensure proper fit and function. If you suspect there is an issue with your vehicle’s NOx sensor, it is best to have it diagnosed and replaced by a certified mechanic.

Here are a few GM NOx sensor part numbers and the compatible vehicles they are used in:

  • 1. 12678993 – Cadillac CT6 2018-2020
  • 2. 55502674 – Cadillac XTS 2013-2019
  • 3. 12677836 – Chevrolet Cruze 2014-2015
  • 4. 555019 – GMC Sierra 2010
  • 5. 12676661 – Chevrolet Malibu 2016-2018
  • 6. 12657188 – Chevrolet Cruze 2011-2014
  • 7. 12617393 – Buick LaCrosse 2010-2016, Chevrolet Malibu 2013-2015
  • 8. 12650660 – Chevrolet Camaro 2010-2015
  • 9. 12678787 – Chevrolet Silverado 2017-2018
  • 10. 12668260 – Cadillac CT6 2016-2017
  • 11. 12645660 – Chevrolet Silverado 2011-2016
  • 12. 12635273 – Chevrolet Sonic 2012-2014, 2016
  • 13. 12641748 – Chevrolet Silverado 2016
  • 14. 555038 – Chevrolet Impala 2014-2016
  • 15. 12672678 – Chevrolet Colorado 2016-2018, GMC Canyon 2016-2018
  • 16. 12611384 – Buick Enclave 2008-2017, Chevrolet Traverse 2009-2017, GMC Acadia 2007-2016, Saturn Outlook 2007-2010
  • 17. 55502672 – Cadillac SRX 2010-2016
  • 18. 12642459 – Chevrolet Camaro 2016-2018
  • 19. 12662738 – Chevrolet Express 2012-2014
  • 20. 12657142 – Chevrolet Spark 2014-2015
  • 21. 555014 – Cadillac DTS 2011
  • 22. 12622959 – Chevrolet Malibu 2010-2012
  • 23. 12666371 – Buick Regal 2012-2015
  • 24. 12684830 – Buick Envision 2016-2017
  • 25. 12672755 – Chevrolet Silverado HD 2015-2016
  • 26. 12677670 – GMC Yukon 2015-2016
  • 27. 12676126 – Buick Encore 2016-2017
  • 28. 12631371 – Chevrolet Volt 2011-2012

GM NOx sensors that are compatible with marine engines:

  • 1. 12673750 – Mercury Marine engines, model years 2018 and later
  • 2. 12657113 – Volvo Penta Marine engines, model years 2011-2014
  • 3. 555005 – Mercruiser Marine engines, model years 2009-2013
  • 4. 12600468 – Yanmar Marine engines, model years 2006-2013
  • 5. 12621460 – Detroit Diesel Marine engines, various model years
  • 6. 12634822 – Cummins Marine engines, various model years