O2 Sensor Predicament
I've been getting some trouble codes from my car for the past couple weeks: P0171 and P0125 mainly. I had some misfire codes too which were taken care of. My mechanic replaced the plenum and throttle body gaskets and ensures me there are no vacuum leaks and no more misfires.
HERE'S WHERE IT GETS TRICKY.
He tells me the 2 upstream O2 sensors are fluctuating identically. I guess normally they are off by a little bit. Also he tells me that they only range from 0-5 volts. My Haynes says 0-1 volt and personal experience tells me 0-10 volts. So which is correct? Also, how do you test the rear bank sensor...its so tight back there.
Also the P0171 and P0125 are still on. The mechanic suggests this could be from the downstream O2 sensor which is completely dead. Is this possible??
Any help as to the root of these codes is appreciated. Thanks!
HERE'S WHERE IT GETS TRICKY.
He tells me the 2 upstream O2 sensors are fluctuating identically. I guess normally they are off by a little bit. Also he tells me that they only range from 0-5 volts. My Haynes says 0-1 volt and personal experience tells me 0-10 volts. So which is correct? Also, how do you test the rear bank sensor...its so tight back there.
Also the P0171 and P0125 are still on. The mechanic suggests this could be from the downstream O2 sensor which is completely dead. Is this possible??
Any help as to the root of these codes is appreciated. Thanks!

- kwyse
- Regular SolaraGuy Member
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- Joined: Tue May 30, 2006 3:14 pm
- Location: Buffalo, NY