Hi guys

I've got a check engine light on. I went to Autozone and they showed an active P0135 fault code. A P0053 was not active but was still showed up on the scan.

P0135 says it's an O2 sensor, sensor 1, bank 1. I don't have experience with H2's, is this the most likely problem?

If so, where is the sensor located, is it something I can change out myself, and what's the best manufacturer for this part?

Thanks guys!!

 

ACDelco 2131161 2005 HUMMER H2 6.0L V8 Oxygen (O2) Sensor | RockAuto

GM P/N 12572705 (no. 4 in the diagram)
http://www.wholesalegmpartsonline.co...rimLevel=25319

 

That is good advise from Citiboy. While you could have other issues causing an 02 sensor code, such as a vacuum leak or bad injector. The 02 sensor is most likely the culprit and sense it is cheap and easy to replace I would start with a new AC Delco sensor.

O2 sensors can degrade over time so replacing them is good preventative maintenance.

 

Thanks guys. Is the sensor accessible and do I need a special tool to remove it?

 

7/8 wrench fits most 02 sensors. Should be fairly easy. They do not need to be tightened very much. install like you would a spark plug.

 

Thanks Phil

Last question. I believe there are four sensors, the fault is showing bank 1 sensor 1. Which sensor is this?

 

Left side pipe, the one above the cat. it's number 4 in the picture like citiboy showed you.

 

Thanks Phil!

 

Although I've got the fault code for just one bad sensor, is it a good idea to replace all 4 sensors? Rig has 125k on it.

 

The two upstream sensors are the more important of the four. I would replace both of them at least.