Bank 1 O2 Sensor

[djmarch]

So my 2004 thru a code telling me "Bank 1 O2 Sensor malfunction". Can anyone tell me if this is the upstream or downstream O2 sensor ?

Thanks in advance

[avguy]

What is the code? Each of the various codes should be associated with a specific sensor, and the doc will tell you which one it is. However, both O2 sensors are bank 1.

[djmarch]

What is the code? Each of the various codes should be associated with a specific sensor, and the doc will tell you which one it is. However, both O2 sensors are bank 1.

Thanks for the reply Avguy...Yes...you are correct...The more research I did, told me bank 1 could be both sensors. The code I got was P0130. That's all my autoxray scanner displayed was bank 1 O2 sensor malfunction. What doc are you referring to ?

[avguy]

A web search will give you a few sites that describes what the code is for, and they show that P0130 is one of the upstream O2 sensor codes. Before hanging on a new one, examine the connector and wiring for defects first, and if you have a multi meter you can measure the sensor resistance, which might confirm it's going bad.