OBD codes / P0102 / Nissan Altima
P0102 on a Nissan Altima
Mass Air Flow (MAF) Circuit Low Input
QR25 and VQ35 Altima.
What P0102 usually means on a Altima
P0102 means the Altima's mass-airflow sensor is reporting an abnormally low signal, and Nissan MAF sensors are a well-known weak point across these engines. A dirty or failing MAF throws off the air measurement, causing hesitation, stalling, or poor economy. It often pairs with lean or rich fuel-trim codes. Cleaning the sensor can help, but a drifting MAF frequently needs replacement.
Most likely causes on this model
- Dirty or failed MAF sensor
Nissan MAF sensors commonly contaminate or drift, reading low and setting P0102.
- Intake leak before the MAF
Unmetered air or a loose air-box connection skews the signal.
- Wiring or connector fault
A corroded MAF connector drops the circuit low.
- Restricted air filter
A heavily clogged filter reduces measured airflow.
What it costs on a Altima
Try cleaning the MAF with proper sensor cleaner first - nearly free and sometimes sufficient. A replacement MAF is a moderate Nissan part and a quick swap. Check the air-box connection and connector before spending, since a simple intake leak can mimic a bad sensor.
Year, engine and mileage change the answer. Get a diagnosis for your Altima — it weighs these causes against your exact configuration and real complaint data.
Diagnose my Altima free →Other codes we cover on the Nissan Altima
Nissan Altima problems & recalls by year
Based on widely reported patterns for this model; individual causes vary by year, engine and history. Generic P0102 behavior is covered on the main P0102 page. Confirm with a scan tool before buying parts.