P0102Powertrain
Mass air flow circuit low input
Where to start
The mass airflow sensor reports less air than the engine actually takes in. Start with the air filter and the duct behind it: a clogged filter or a cracked intake hose produces this code with the sensor itself perfectly fine. The sensing wire can also be fouled by oil from an over-oiled performance filter.
What to watch in live data
A code is not a diagnosis. It says which check failed, not which part to replace. Clearing it without repair only means the car will report it again in a few trips.
How to put together a report a mechanic will actually read
We have a detailed piece on thisThe MAF sensor: signs of wear and a live-data check
How the code is built
Letter — the systemPowertrain: engine and transmission
Common or the maker's ownGeneric code: the same on every car
Which part of the engineFuel and air metering
Number of the faultThe serial number inside that group — it does not say how serious the fault is
All codes in «Intake measuring sensors»
How the app helps
CarScan reads this code from your car through an OBD-II adapter, shows whether it is active now or only stored, names the module that reported it, and puts it into a plain-text report for your mechanic.