Fuel and air metering
P0102 — Mass or Volume Air Flow Circuit Low Input
The MAF sensor signal voltage is lower than the expected range. The ECU thinks very little air is entering the engine and delivers the wrong fuel quantity.
Common causes
- Faulty or dirty MAF sensor
- Open circuit, damaged wiring or poor connector contact
- Loose or missing sensor ground or power supply
- Air intake leak or restriction
- Water or oil contamination in the connector
Symptoms
- Stalling or hard starting
- Rough idle
- Weak acceleration
- Check engine light
How to check
- Inspect the MAF connector and wiring for damage and corrosion
- Check the sensor's supply voltage and ground
- Read live MAF values and compare them with a known good sensor
- Clean or replace the sensor if its signal stays too low
Can you keep driving?
Drivable for short distances, but performance will be poor and may stall. Repair it soon.
Related codes
Frequently asked questions
- What does P0102 mean?
- The mass air flow sensor is sending a signal that is lower than the normal range.
- Is P0102 always a bad sensor?
- No. Wiring, connector and ground faults can cause the same code, so test the circuit first.
General reference information. It does not replace a diagnosis on your own vehicle. The same code can have different causes depending on make, model year and engine; check the manufacturer's documentation or ask a technician with a scan tool.