P0101 Code: Mass or Volume Air Flow (MAF) Sensor Circuit Range/Performance

🟠 Moderate severity · drivable

Drivable short-term, but a wrong air reading can cause rough running and poor fuel economy, so fix it soon.

What P0101 means

The mass air flow (MAF) sensor is reporting an airflow reading that's outside the expected range for the current engine conditions. The MAF tells the computer how much air is entering so it can add the right amount of fuel; a bad reading throws that calculation off.

Symptoms

Check engine light is on
Poor acceleration or hesitation
Rough or unstable idle
Stalling
Poor fuel economy

Common causes

most common: Dirty or contaminated MAF sensor
common: Vacuum leak after the MAF sensor
common: Faulty MAF sensor
less common: Clogged air filter
less common: Wiring or connector problem at the MAF sensor

How to fix it

Fix	DIY?	Typical cost
Clean the MAF sensor with MAF cleaner spray	Yes	$10–20
Replace a clogged air filter	Yes	$10–30
Repair any vacuum leaks	Yes	$10–100
Replace a faulty MAF sensor	Yes	$80–300