On a 2001 Pontiac Grand Am GT (3.4L 6 cylinder), is the 'Bank 1, Sensor 1' oxygen sensor the upstream or downstream sensor? From what I've looked up it appears to be the upstream sensor, I just want to make sure so I don't buy the wrong part. Thanks a lot!
I took it to a family friend who ran diagnostics on it and was told to get a Bank 1, Sensor 1
position Oxygen sensor. From what I understand the Grand Am has two oxygen
sensors.. one upstream and one downstream. From an internet search I've seen 'Sensor
2' referred to as downstream which leads me to believe that Sensor 1 would be upstream.
Let me know if I can provide any more info that would help.