Pulled the code today, and got P0171, code for bank 1 running lean, and not sure if the front or rear is 1. As for the code, I'm not sure what set it off, could a bad coil set this code off, or am i looking at fuel delivery problems?

 

Actually, I have 2000 SE and have the same engine code as well. Mine is Cali spec. When I measured the resistances of the O2 sensors, three of them gave around 4.2 ohms while the right-most (looking from the front of the car) O2 sensor's resistance was infinite. The car was off when I did this and I don't think those oxygen sensors reached their operating temperatures yet.

My questions are:

1. Was that a valid way to test the O2 sensors?
2. Does the right-most O2 sensor correspond to the rear? When I tracked the wire down, it did go to the rear of the engine.
3. Can a bad O2 sensor throw this code while having the O2 sensor code (138?) not thrown?
4. Is something else wrong? (coil, fuel delivery as SkylineGTR is suspecting)

 

The rear should be 1 where the #1 cylinder is.

 

REAR
135
246
FRONT

 

Hi,

Well it sounds like that might be a bad 02 or a short. The real way to test them is by injecting kerosene into the lines and the resistance should instantly react to the leaner mixure and direct the ecu to run richer. Under load with the car running is how I have always tested them and it is how the dealer will test it. The pocket PC can be misleading. The codes can be wrong. Sometimes the ECU needs a reflash. It might be cheaper to just go to a good dealer if you can find one. Those sensors are not cheap $140 each. It may not be one, especially on a 2000.

 

I have a 2000 i30 with the same MIL code. I've reset it twice, but keeps coming back. No drivability issues though. please let me know if you found the solution. thanks

 

rear LEFT.........

 

I thought bank 1 is the front and bank 2 is the rear. I just got a code for bad sensor, bank 2 sensor 2. So I bought the rear senser after the pre-cat.

 

That's right... I think its in the owners manual