Air intake
Mass Airflow Sensor
The MAF sensor measures how much air the engine is breathing so the ECU can meter fuel.
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Air intake flow
Interactive — tap a partTap a part to see how it fits in the system.
What it does
- Measures intake air mass or volume
- Lets the ECU set the correct air-fuel ratio
- Warm wire type self-cleans by heating
When it fails
- P0101–P0103 codes
- Rough idle
- Poor acceleration
- Higher fuel consumption
How to diagnose
- Clean the element with MAF cleaner
- Read live MAF grams/sec at idle
- Compare with spec for the engine size
- Inspect for oiled filters that foul the sensor
Maintenance
- Clean periodically in dusty conditions
- Avoid oiled air filters on MAF cars unless designed
- Never touch the element
Use the diagnosis order. When a part fails, confirm each hypothesis with measurements before replacing anything — codes and symptoms overlap.
Related part
Air Filter
The air filter cleans the air entering the engine before it is metered by the MAF.