Not sure what forum to put this in.. If it needs to be moved, I understand. I posted here cause there is a lot of knowledge about this problem, just not this platform.
So my wives Pontiac Aztek has been throwing a code for a O2 sensor for over a year now. This V6 only has 2, one upstream, and one downstream. The upstream is the one that keeps throwing the light.
Truck runs like a top, always starts, no extended start times. New plugs and wires as well.
I checked the LTFT and STFT, and everything checks out like it should, but thought it was maybe a lazy O2 sensor, so replaced it with another ACDelco model from Amazon. Check engine came back.
Thinking maybe it was a Chinese Amazon clone, I threw a ACDelco in from NAPA, but downstream and upstream. The light came back.
I can reset the MIL light, and all is fine, until she gets on the highway, and then in about 20-30 minutes, the light is back on.
I cant gauge whether or not its related to her fuel mileage, she doesnt drive enough.. Her average is 11-13 mpg. Truck used to get 18-23, but she also drove it A LOT more. She only drives about 1600 miles a year. Yes, one thousand six hundred miles.
There are no other MIL lights or codes, and as far as I can tell, the O2 sensor is working as it should.
Emissions is next month, and a check engine light is a automatic failure.. This wont do.
Im not sure what else to try.. A Catalytic Converter?
Help?!
So my wives Pontiac Aztek has been throwing a code for a O2 sensor for over a year now. This V6 only has 2, one upstream, and one downstream. The upstream is the one that keeps throwing the light.
Truck runs like a top, always starts, no extended start times. New plugs and wires as well.
I checked the LTFT and STFT, and everything checks out like it should, but thought it was maybe a lazy O2 sensor, so replaced it with another ACDelco model from Amazon. Check engine came back.
Thinking maybe it was a Chinese Amazon clone, I threw a ACDelco in from NAPA, but downstream and upstream. The light came back.
I can reset the MIL light, and all is fine, until she gets on the highway, and then in about 20-30 minutes, the light is back on.
I cant gauge whether or not its related to her fuel mileage, she doesnt drive enough.. Her average is 11-13 mpg. Truck used to get 18-23, but she also drove it A LOT more. She only drives about 1600 miles a year. Yes, one thousand six hundred miles.
There are no other MIL lights or codes, and as far as I can tell, the O2 sensor is working as it should.
Emissions is next month, and a check engine light is a automatic failure.. This wont do.
Im not sure what else to try.. A Catalytic Converter?
Help?!
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