I don't post a lot due to soaking in the knowledge that gets posted. Ok here's the back story. 2008 with 4.7 73000 miles and the o2 sensor went off when the temperature hit below zero couple weeks ago about minute after start up. Scanned it and changed the sensor with Bosch. Stayed off until same thing happened about a week later again below zero temp at start up. Did some reading found that bosch no good so got the ngk. Put that in and started no problems in below zero for couple days. Today same thing happened about minute running and same sensor goes off. Clear code start it and sensor stays off. Smelled exhaust and doesn't smell like anything is running terrible rich or burning oil or other fluids. Really getting upset due to when trying to use factory car starter to warm the truck before putting a young child in the truck and it won't work due to the check engine keeps going off and shutting the truck off. Runs fine and the O2 sensor stays off but will only trip when it is extremely cold out first start of the morning. By the way truck sits outside. Thanks for any help

 

I think I may have changed the wrong side. My code was Bank 1 sensor 2. I changed the passenger side post catalyst. I am now thinking I should have done the driver's side.

 

Yup change it to the other side

 

thank you very much for the confirmation.

 

Thanks to joebaum for the assistance with which sensor. -9 this morning and no code. my little girl very happy to get in a warm truck.

 

Just keep in mind just because you're getting a DTC code related to an O2 doesn't mean it is the O2. For instance, a broken or blown exh manifold gasket will allow fresh air to be sucked into the exhaust which will go by the O2 and will give an O2 code but the O2 is actually working as it should.