Oxygen sensors

[tj011673]

Hey all,

I believe the trouble code I had read from my GP says there is an O2 sensor issue. I believe there are 4 of them. 3 upstream before the Cat and 1 after the Cat downstream. Is there any way to know which one(s) is(are) bad? I would hate to have to spend the money to get them all changed if it is only one causing an issue.

Any help is greatly appreciated!

Thanks!

Tim

[dsmuts]

Which code do you have? What do you drive? There are only 2 o2 sensors on there.

[Frosty]

If you have a grand prix there are 2 o2 sensors. One before one after. The one after the cat is absolutely useless and most people bypass it. The one before is vital.

[tj011673]

Thanks Dsmuts and Frosty,

I have a 2001 Grand Prix. 3.1 V-6. I can not remember the code number off hand. I am going use the code reader on it again tomorrow some time to get the code once more and make sure nothing new has popped up. I don't think I can bypass the downstream O2 as I live in NYC and have to get an inspection before registering the vehicle. I am pretty sure I need to make sure my CAT and the sensors are working. Thanks for the info though. I saw a diagram of the exhaust that showed 4 sensors. as i said above 3 in bank 1and 1 in bank2. I appreciate the input... I won't go crazy looking for the other two.

[Frosty]

In south dakota we dont get checked .... No cat.... Or egr... Or evap..... Lol

[BillBoost37]

Tim..

It might be worth it to meet up with Oldsman105 and Buickman104, they are also both NYC guys and have a programmer etc that may help you figure it out.

[jrvl93]

if whatever scanner you are using doesnt tell you which sensor has an issue then get a different scanner it should say for example P0xxx whatever the code is then say for example HO2S Heater circuit High/Low sensor 2 which is the rear sensor. The rear sensor is basically useless it just compares data with the front sensor however if the front sensor goes you will definetly notice because your car will run like a pile of dung because the ecm receives a bad signal or no signal at all screws of the fuel trim data and makes the engine buck the a spurred mule

[BillBoost37]

We have bank 1 sensor 1 (in rear exhaust manifold) and bank 1 sensor 2 (post cat). No bank 2 sensors exist.

[jrvl93]

i never said bank 2, i said sensor 2 lol

[BillBoost37]

i never said bank 2, i said sensor 2 lol

Not saying anything about what you said. Only informing the op of what exists on his car, that way he has a better understanding if someone says bank 2 or sensor 2. Sometimes folks that are new to this believe the terms are the same thing.

Only thing I'd suggest for you is typing a little cleaner.. but heck..you got your points across just fine.

[jrvl93]

Not saying anything about what you said. Only informing the op of what exists on his car, that way he has a better understanding if someone says bank 2 or sensor 2. Sometimes folks that are new to this believe the terms are the same thing.

Only thing I'd suggest for you is typing a little cleaner.. but heck..you got your points across just fine.

ohhh oops my mistake lol and ya i never was good at explaining things English class in high school wasn't my strong suit