P0102
MAF Sensor Circuit Low Input
medium
i Description
The Mass Air Flow sensor is reporting a lower-than-expected voltage or frequency to the ECU. This typically means the sensor is reading less air than is actually entering the engine.
? Common Causes
- Dirty or failed MAF sensor
- Open or shorted wiring to MAF sensor
- Air leak after the MAF sensor
- Faulty ECU (rare)
- Corroded MAF connector pins
! Symptoms
- Check engine light
- Engine running rich
- Black exhaust smoke
- Poor acceleration
- Stalling
# Diagnostic Steps
- Inspect MAF sensor connector for corrosion or loose pins
- Test MAF sensor voltage at idle (should typically be 0.5-1.0V)
- Check wiring between MAF and ECU for opens or shorts
- Clean MAF sensor element
- Test with known-good MAF sensor
⚙ Typical Fix
Repair wiring to MAF sensor or replace the sensor itself.
Parts Needed
MAF sensor, Wiring repair supplies
Estimated Cost
$50-$350
↔ Related Codes
Q Frequently Asked Questions
You can drive carefully, but the engine will likely run rich and performance will be poor. Extended driving in this condition can foul spark plugs and damage the catalytic converter.
Wiring repair: $50-$150. New MAF sensor: $80-$300.
☞ Learn More
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