P0102 - Mass or Volume Air Flow Circuit Low Input
MAF signal voltage/reading is too low.
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Common Next Steps
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Compare trims at idle, 2500 RPM, and cruise before pricing sensors.
Check intake boots, PCV hoses, and post-MAF leak paths.
Inspect MAF contamination and airflow data after intake leaks are considered.
Look for cracked ducts, loose clamps, and unmetered air after the MAF.
Related Inspection
Code Overview
MAF signal voltage/reading is too low.
Common Causes
- Unplugged or failing mass air flow sensor
- Wiring open or short to ground in the MAF circuit
- Air intake restriction reducing measured airflow
- Unmetered air leak skewing the signal
Symptoms
- Hesitation or weak throttle response
- Rough idle or lean stumble
- Poor fuel economy or reduced power
Diagnostic Steps
- Make sure the MAF connector is fully seated and the terminals are clean
- Inspect the harness for opens, rubbed-through spots, or poor ground
- Check the air filter and intake ducting for restriction or collapse
- Compare MAF data to expected airflow at idle and snap throttle
Repair Difficulty
Moderate
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Next Steps
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