O2 sensor enlightenment.
I immediately noticed how smooth my car is running with the new sensor. My engine has gotten quieter as well. I was pretty much due for a new one since I'm at 92k. My initial thought is that my o2 sensor was on the edge of failure for the last 10k miles but it wasn't until I tracked it that I pushed it over the edge. Either way I'm glad I changed it out and my car really feels good.
As for the o2 sensors, this is the run-down...
-I put the rear spec o2 sensor ($80) equivalent in on the drive up...no go it gave me the same no signal error.
-I repinned and put the $20 sensor. It gave me an electrical malfunction error
-I swapped the heater wires on it. It still gave me an electrical malfuntion error.
- I started ohming out the sensors ($80/$20/OEM sensor). The heater wires were the only ones that could be ohmed out. The $20 was 10.7 ohms and the OEM and rear spec cat ohmed out to ~3.5ohms. However, according to Bentley, both values were valid.
-I then swapped the $80 sensor again just to see if the original no signal DTC code would return. However, I started doing continuity checks between the connector pin and wire at the back end just to make sure and I also yanked the ECU and let it sit for about 3 hours. Once I put everything back in and I drove around again, the error did not reappear. It looks like the rear sensor was fine to use after all! The best part was that the engine really smoothed out and the normal excessive soot I collect at the tips was minimized to almost nothing. Thanks to you and Greg for the idea. I think Greg's theory was right that the O2 sensor starts to degrade over time and really make the car run like crap.
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