Oxygen Sensor Locations

[CrazyJoey]

I hooked up a OBDII scanner to my wife's 2006 GMC Sierra SLE because it had a code. The code was P0154 - No activity on O2 Sensor Bank 2 Sensor 1.

 

I see the four sensors from underneath the truck, but....where is Bank 2 Sensor 1? Is that the driver's side pre-cat O2 sensor, or the passenger's side?

 

I talked to a local GMC dealer's parts department, and the guy said that when it says Bank X Sensor Y on the OBDII scanner/reader you're using....the X is the cylinder number, and the Y is....well...we know what that is.

 

Is this true? Thanks for your help.

[vortec350]

Bank 2 sensor 1 is passengerside IN FRONT of cat,furthest one upstream

Bank 1 is driver side

Sensor 1 is upstream and sensor 2 is downstream (after cats)

[jrrod2004]

This should help in the visual aid:

 

http://www.gm-trucks.com/forums/index.php?...icle&id=769

[bill190]

I've seen some of these sensors go "upwards" from the exhaust piping. So if you just look under the vehicle from the side, you will not see it!

 

Basically you need to crawl under the vehicle and look at both sides of the exhaust pipes from underneath.