Hello I had a check engine light come on so I took my Blazer and had my friend test it on his computer. It says I have a Bad O2 Sensor Bank 2 Sensor 1, I guess there are 4 o2 sensors? I would hate to change the wrong one lol I checked AutoZone they want 70 bucks ! I found one cheaper on ebay. Maybe someone could check it out and see it it is the right part for me? i would really appreciate your help Thanks


NEW DIRECT FIT O2 OXYGEN SENSOR REPLACEMENT PRE POST CAT FITMENTS AIR FUEL RATIO | eBay

 

There are only 3 sensors on your truck. We would need the specific code (Pxxxx) to help diagnose the issue, but as a diagnostic step, you could swap the O2 sensors side to side. Bank 1 sensor 1 and bank 2 sensor 1 are both between the exhaust manifolds & the 'Y' in the y-pipe. Bank 2 is the passenger side bank. Swap B1S1 to B2S1 and see if the code changes to indicate B1S1 as the problem.

As far as replacement O2 sensors go, I am partial to AC Delco, but NTK, Denso, & Delphi are also high quality sensors that work well in these trucks. My experience with Bosch has been nauseating so I stay clear of them as well as all of the other no-name brands.

 

Thanks Swartlkk ! Im gonna give that a shot. I was also told by another guy stay clear of Bosch. Gave ya some rep