P1283 Infiniti Code - Air Fuel Ratio Sensor 1 Lean Shift Monitoring Bank 2

I have replace all the O2 sensors in the system. I will be looking at the Mass Airflow sensor next. The car has about 180,000 mile on it now. When I did replace the O2 sensors it made a difference in the mileage, it improved. I don't want to believe that I have a new O2 sensor gone bad just after installing it. What should my reading be for the O2 voltage after warm up, Idle then at higher RPM?

What model and year is your Infiniti?

The P1283 is for the Air Fuel Ratio (A/F) Sensor 1 Bank 2, which sensor did you replaced?

If you have only the P1283 code, then just replace the Air Fuel Ratio (A/F) Sensor 1 Bank 2 sensor.

This is an 04 Infinity FX35 It has codes p1273 and P1283. I have replaced all the O2 sensors. This is why I am steering to another part that will cause this code. Also wanted to note that I have changed the fuel injectors before and they only have about 10k miles on them. I will also check for a line off of the intake manifold to see if maybe I pulled off a vacuum line from the intake while getting to the O2 sensors. I did not see any other obvious signs that could give me any problems. I still need to check the fuel pressure as well.

How long it takes for the codes to come back after you replaced the sensors?

I test drove the car for about 1/2 hour after replacement. Then the next day going to work the light came back on. I checked the code and did a reset then it took about 15 to 20 miles and the code came back on. I did notice while idling that the RPM stumbled a couple of times but then returned to normal. The RPM stumble was not constant and only happened a few times that I saw.

Other than the Air Fuel Ratio Sensors, the only other thing that I have seen that could trigger both codes is the Mixture Ratio Self-Learning Control Data. You should perform a Mixture Ratio Self-Learning procedure before replacing any other parts. Also make sure there are no intakes or exhaust leaks near the sensors.

2003-2012 Infiniti FX Clear Mixture Ratio Self-Learning Control Data
Instructions here: https://www.infinitihelp.co...

Hello, I have this code p1283 also. 04 g35x. Can you point me in the direction of a diagram as tp where it is located ? I know its drivers side. I read there is 2. Is it the one up high before the cat ? or down lower after the cat ? And if i have some type of an exhaust leak would this make the CEL come on ? I just bought the car and some kind of weird noise like a bad cat converter like a rattling sound after it warms up. Or could just be a loose exhaust mount and the muffler is rattling. I'm not sure. Thank you !

Hello, I have this code p1283 also. 04 g35x. Can you point me in the direction of a diagram as to where the AF sensor is located ? I know its drivers side. I read there are 2 of them. Is it the one up high before the cat ? or down lower after the cat ? And if i have some type of an exhaust leak would this make the CEL come on ? I just bought the car and some kind of weird noise like a bad cat converter like a rattling sound after it warms up. Or could just be a loose exhaust mount and the muffler is rattling. I'm not sure. Thank you !

The A/F Sensor is before the Catalytic Converter. (See image below). Exhaust leaks could set the codes. So if the catalytic converter is rattling or you ave an exhaust leak, fix that problem first.

Hello Is there a way to test the sensor and see if its bad ? And the rattling noise is that a bad convertor ? Do you have a better image ? i don't get where this is ? am i looking up from under the car in this ? thank you and thanks for the fast reply !

The only way I know you can monitor the A/F sensor is with the Nissan CONSULT or a high end OBDII Scanner.

Unfortunately without hearing the rattle noise I can't suggest where the noise is coming from or what the problem is.

That is the only image I got.