I have a 2001 Pontiac Gran am gt 3.4. the original codes were p0131 and p0141 i unplugged and re plugged in sensors and i now have p0131 and p0171. i just purchased a new sensor with wiring and am hoping this will solve the issue . does and one have any ideas. the other issue i have is after the car warms up when the car is in park the car idle drops and go up constantly.

What did you unplug and replug back in? What sensors did you replace. Please help us out by telling us exactly what you did, vague statements like these aren't very helpful.

Unplugged and replugged in o2 sensors. i have not replaced the o2 sensor that'* giving the p0131 code yet. it got to late last night. will be doing soon.

You can try and change out the Bank1 sensor, but I think your looking at a vacuum leak somewhere.

we will be replacing the o2 sensor tonight. could not track down a vacuum leak. but will try again.

How is the coolant level?

Got sold a bad o2 sensor changed it and all the issues went away. even passed emissions. Thanks for all the help.

Thanks for the update.