Fault-Code Library · Air metering
P0102: Mass-air-flow circuit low input
The MAF sensor signal is lower than expected for the engine speed and load.
Common symptoms
- •Low power
- •Rough idle
- •Poor fuel economy
- •Smoke on acceleration
Likely causes
- •Disconnected or failed MAF sensor
- •Wiring or ground fault
- •Intake restriction
- •Air leak or incorrect sensor reading
First checks
- •Inspect the MAF connector and intake tract
- •Compare MAF grams-per-second with expected values
- •Check power, ground, and signal wiring
Important
A low MAF signal can come from wiring, airflow restriction, or air leaks, not only the sensor.
A fault code identifies a detected condition, not a failed part. Confirm manufacturer-specific subcodes and live data.
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