P0101: Mass or Volume Air Flow Circuit Range/Performance
Short answer: P0101 means “Mass or Volume Air Flow Circuit Range/Performance”. It is a standard OBD-II code, so the basic meaning is the same on every car. Below is what it means on each of the 5 cars we cover, with a link to the full page for each car.
Standard OBD-II code Same meaning on all cars (SAE J2012).
P0101 on each car
| Car | Meaning on this car | Confidence |
|---|---|---|
| Toyota Corolla (11th gen, E170) | Mass or Volume Air Flow Circuit Range/Performance | medium |
| Toyota Corolla (10th gen, E140) | Mass or Volume Air Flow Circuit Range/Performance | medium |
| Honda City (5th gen, GM2) | Mass or Volume Air Flow Circuit Range/Performance | medium |
| Honda Civic (10th gen, FC) | Mass or Volume Air Flow Circuit Range/Performance | medium |
| Suzuki Wagon R (Pakistan, K10B) | Mass or Volume Air Flow Circuit Range/Performance | medium |
Symptoms
- Check engine light on
- Rough running engine
- Black smoke from tail pipe
- Stalling
- Engine hard start or stalling after it starts
- Possible other driveability symptoms
Likely causes
- Fault in the part or circuit named in the code
What to check, in order
- Read the code and freeze-frame data with an OBD-II scanner
- Check the connector and wiring of the part named in the code
- Test the part with scanner live data or a multimeter, using the values in the repair manual
- Fix the cause, clear the code and test-drive
Causes and checks above are the general meaning. The exact test steps and values differ by car: open your car’s page.

