OBD-II FAULT CODE
P0101: Mass or volume air flow circuit range/performance
Fuel and airGeneric powertrainThe reported air flow is inconsistent with the expected operating range. The sensor, intake path, wiring and other engine conditions require assessment.
Possible causes
Examples to investigate; this list is not a probability ranking or a diagnosis.
- Air leaks or restrictions in the intake
- Contaminated or incorrectly reading air-flow sensor
- Wiring or connector problems
Symptoms you might notice
- Check-engine light
- Hesitation, unstable idle or reduced power
Diagnostic approach
- Inspect the air filter, intake ducting and connections.
- Compare air-flow data with engine load and manufacturer reference values.
- Test power supply, ground and signal using the correct wiring diagram.
Save codes and freeze-frame information before clearing anything. A cleared warning light does not prove that a repair worked; the applicable monitor must run again.
Possible repairs — after testing
- Correct a verified intake leak or restriction.
- Repair wiring or replace the sensor only after tests support that repair.
Related codes
This is general diagnostic orientation, not a manufacturer-specific repair procedure. A qualified technician can confirm test conditions and safe working methods.