Diagnostic guidance. Suggested checks and possible repairs are separate from the owner's reported results.
Record the remaining symptoms, current code status and operating conditions for the fuel-trim readings, then have the results evaluated using the Nissan diagnostic procedure. Confirm which upstream sensor was installed and whether the original concern remains. The reported improvement does not isolate which of the two actions helped. Continued driving or replacing the mass-airflow sensor should not be presented as a confirmed solution to the remaining concern.
2CarPros: Original discussion 1712592 https://2carpros.com/questions/2017-altima-with-dtc-codes-p015a-p015b-p014c Source for the owner's reported history and outcome. Contributor suggestions are not independently confirmed diagnoses. No attachment content was verified.
2017 Altima with Dtc codes P015A , P015B , P014C?
The owner of a 2017 Nissan Altima 2.5 reported codes P015A, P015B and P014C. After cleaning the mass-airflow sensor and replacing the upstream sensor, the owner said the permanent codes disappeared. Short-term fuel trim at idle was still reported at approximately minus twelve to minus fifteen percent.
Reported outcome: The owner reported that the codes disappeared, but the fuel-trim concern remained unresolved in the discussion.
No follow-up readings, exhaust-leak test or completed diagnostic report were supplied. The original code descriptions and the prediction that the readings would normalize were not independently verified.
