OBD-II code guide

P0100 Mass or Volume Air Flow Circuit

P0100 means the mass airflow circuit has a general electrical or signal fault.

What it means

The engine computer cannot reliably use airflow information for fueling calculations.

Common symptoms

  • Hesitation
  • Rough idle
  • Poor fuel economy
  • Stalling
  • Check engine light

Likely causes

  • Dirty or failed MAF sensor
  • Loose intake duct
  • Wiring issue
  • Connector corrosion
  • Air leak after the sensor

First checks

  • Inspect the intake boot after the air filter.
  • Check MAF connector fit.
  • Look for other lean or rich codes.
  • Avoid spraying harsh cleaners on the sensor.