2004 GMC Yukon XL Denali Q&A

2004 GMC Yukon XL Denali Question: o2 sensors

Replaced bank 1 sensor 2, bank 2 sensor 2 and computer still reads same sensor problem. What else could it be? Thank you! -
Answer 1
Oxygen sensors are identified by bank and sensor position. Sensor 1 is always pre catalytic converter, sensor two is always post catalytic converter. If an engine is a 4 or 6 cylinder engine the whole engine is considered bank 1, if an engine is a V6, V8, V10....., the engine bank containing cylinder number 1 (first cylinder in the firing order) is considered Bank 1, the other bank is considered Bank 2. Interpretation Oxygen sensor designation B2S1 refers to Bank 2 Sensor 1, it will be the sensor on the engine side of the catalytic converter in bank two. Check this link to determine the cylinder that contains cylinder number 1. http://www.wellsve.com/custom_searches/ds_firing.php -
Comment 1
Yes, thank you they were put in the right spot, but computer still comes up o2 sensor problem. Could it be due to fuses? -
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