Have been doing some reading about P0431 codes...
I got one a few months ago. It came and went a few times.
Seems like it could be my downstream O2 sensor, judging from some posts around the web. Or, it could be something else (vacuum leak? cat itself? precat? a timing belt? spark plugs?)
However, the car hesitates more and more now (since last month) and struggles to get out of 2nd gear but still has plenty of power after the hesitation. Would a faulty downstream O2 sensor still cause this? Or the neutral safety switch? TPS sensor?
I'm sure they're all somehow connected.
Here is a video of it struggling to get out of 2nd. It appears to shift into 2nd fine.
https://drive.google.com/file/d/0B3OMmL31IzRHSWVUcF9RcHBWb1U/view?usp=sharing
It is a 2000 Mazda 626 ES V6 with 230k miles.
The EGR valve was cleaned two months ago and all the sparkplugs were replaced with NGK plugs about two years ago.
Here is also a video of some diagnostics I ran on it with Torque pro.
https://drive.google.com/file/d/0B3OMmL31IzRHenhnbXZVaVhDTUk/view?usp=sharing
Fuel Trim:
LTFT1 is long term fuel trim for bank one
F/T 1X1 is fuel trim bank one sensor 1
STFT1 is short term fuel trim for bank one
LTFT2 is long term fuel trim for bank two
F/T 2X1 is fuel trim bank two sensor 1
STFT2 is short term fuel trim for bank two
**NOTE: be sure to check out the second set of these readings in the video, at 2:43... for whatever reason, the long term fuel trim for bank two gets a reading the second time but not the first time.**
Oxygen Sensors:
O2 1x1 is Volts bank 1 sensor 1
O2 1x2 is Volts bank 1 sensor 2
O2 2x1 is Volts bank 2 sensor 1
O2 2x2 is Volts bank 2 sensor 2
Any and all thoughts would be MUCH appreciated.
Thank you so much,
Ty
I got one a few months ago. It came and went a few times.
Seems like it could be my downstream O2 sensor, judging from some posts around the web. Or, it could be something else (vacuum leak? cat itself? precat? a timing belt? spark plugs?)
However, the car hesitates more and more now (since last month) and struggles to get out of 2nd gear but still has plenty of power after the hesitation. Would a faulty downstream O2 sensor still cause this? Or the neutral safety switch? TPS sensor?
I'm sure they're all somehow connected.
Here is a video of it struggling to get out of 2nd. It appears to shift into 2nd fine.
https://drive.google.com/file/d/0B3OMmL31IzRHSWVUcF9RcHBWb1U/view?usp=sharing
It is a 2000 Mazda 626 ES V6 with 230k miles.
The EGR valve was cleaned two months ago and all the sparkplugs were replaced with NGK plugs about two years ago.
Here is also a video of some diagnostics I ran on it with Torque pro.
https://drive.google.com/file/d/0B3OMmL31IzRHenhnbXZVaVhDTUk/view?usp=sharing
Fuel Trim:
LTFT1 is long term fuel trim for bank one
F/T 1X1 is fuel trim bank one sensor 1
STFT1 is short term fuel trim for bank one
LTFT2 is long term fuel trim for bank two
F/T 2X1 is fuel trim bank two sensor 1
STFT2 is short term fuel trim for bank two
**NOTE: be sure to check out the second set of these readings in the video, at 2:43... for whatever reason, the long term fuel trim for bank two gets a reading the second time but not the first time.**
Oxygen Sensors:
O2 1x1 is Volts bank 1 sensor 1
O2 1x2 is Volts bank 1 sensor 2
O2 2x1 is Volts bank 2 sensor 1
O2 2x2 is Volts bank 2 sensor 2
Any and all thoughts would be MUCH appreciated.
Thank you so much,
Ty