Trouble code
P0101
Mass Air Flow Circuit Range / Performance
What P0101 means
The airflow reading does not match what the computer expects for the current throttle position and engine speed.
Symptoms you may notice
- Hesitation
- Rough idle
- Stalling
- Poor economy
Common causes, cheapest first
- Contaminated mass airflow sensor element
- Air filter fitted incorrectly or over-oiled
- Air intake leak between the sensor and the throttle body
- Restricted air filter
- Vacuum leak
Before you buy anythingClean the sensor with proper MAF cleaner before replacing it. Over-oiled aftermarket performance filters are a leading cause of this code, and cleaning the element fixes it for the price of a spray can.
What to do next
- Confirm the code with your own scan tool, or have it read free at a chain parts store.
- Decode your VIN so you know your exact engine and build date.
- Work down the causes above from cheapest to most expensive.
- Search NHTSA for a recall or service bulletin covering this symptom on your vehicle.
- Read the engine buying guide before ordering.
P0101 is a generic OBD-II code, standardized across every make and model sold in the US from 1996 onward. The meaning is the same on any vehicle; the specific part and its location are not.
Parts
Parts commonly needed for P0101
These go to Amazon. We earn a commission if you buy, at no extra cost to you — see our affiliate disclosure. Which one you actually need depends on diagnosis — read the note above first.
Confirm fitment against your VIN on the listing page before ordering. A part that matches your year and model can still be wrong for your build date or engine code.