I would like to ask Sentra experts to help me on this P1126 code on my 2001 Sentra CA model.
This code will come on at any driving condition. The code will come back a few days later after I erased it.
On the servise manual I have, Sentra CA does not have this code.
Would any expert there to tell me what is the problem with my car and what is that mean with the code?
I also used to have a P1275 code for a while which I also have no clue of what that is, but it went away eventually.
I have 80,000 mile on this car.

Thank you for your help.

 

Problem solved!
I replaced the thermostat and the problem was gone at least for a week now.
The thermostat opens too much? The coolent temp was 160 F whenever the check engine light was on.