- Joined
- Feb 2, 2011
- Messages
- 34
- Points
- 1,601
- City
- Salem, Oregon
- Vehicle Year
- 1989
- Transmission
- Manual
Working on my friends Mazda Navajo manual 4 w/od... Either a 94, or 95... with over 200k
I test drove it and there is a hesitation at acceleration, ides at 500 and runs just fine at idle and deceleration, I pulled codes and got KoEo codes 173, and 178:
Oxygen sensor not switching - system is or was rich - Single, Right or Rear HO2S
and
Oxygen sensor not switching - system was rich Left or Front HO2S
Here is my brainstorm.... possible senarios.
1. both o2 sensors are not functioning
2. is the truck simply running rich.
3. does it mean that the first 02 sensor is bad, causing the truck to run rich and causing the rear sensor to read rich....
4. first sensor goes bad, killing catalytic converter, thus killing the last cat
Should I just replace both sensors, are the sensors bad either way? Or is there something further up the line that could cause both not to work.
The exhaust is particularly loud, but could the CAT still be bad?
I certainly appreciate any help. I dont know if this has any value, but he was having other problems and replaced the MAF, which made it run better, could not unplugging the battery after a repair like that make the truck run like this?
thanks,
edit: video got done uploading
I test drove it and there is a hesitation at acceleration, ides at 500 and runs just fine at idle and deceleration, I pulled codes and got KoEo codes 173, and 178:
Oxygen sensor not switching - system is or was rich - Single, Right or Rear HO2S
and
Oxygen sensor not switching - system was rich Left or Front HO2S
Here is my brainstorm.... possible senarios.
1. both o2 sensors are not functioning
2. is the truck simply running rich.
3. does it mean that the first 02 sensor is bad, causing the truck to run rich and causing the rear sensor to read rich....
4. first sensor goes bad, killing catalytic converter, thus killing the last cat
Should I just replace both sensors, are the sensors bad either way? Or is there something further up the line that could cause both not to work.
The exhaust is particularly loud, but could the CAT still be bad?
I certainly appreciate any help. I dont know if this has any value, but he was having other problems and replaced the MAF, which made it run better, could not unplugging the battery after a repair like that make the truck run like this?
thanks,
edit: video got done uploading
Last edited:
