P0102 — Mass air flow (MAF) sensor circuit low input

What this code generally means, its most common causes, and how serious it is.

TYPE: GENERICSYSTEM: AIR-FUEL MIXTURE

What does the code P0102 mean?

The mass air flow (MAF) sensor is sending an implausibly low signal, often close to zero — unlike P0101, which covers a signal that's simply out of range, here the signal is flatly absent or too weak continuously.

Common possible causes

Damaged or disconnected wiring — a common cause of a missing signal.
A corroded or loose connector — poor contact at the sensor.
A failing MAF sensor — no longer producing a usable signal.

General severity

Moderate — worth checking soon

On many vehicles, the control module then falls back to an estimate based on throttle position instead of the MAF sensor — driving is usually still possible, but less precise (rough idle, sluggish power).

This is still a general severity for this code, not a diagnostic for your car. Only a real read of your codes, with your mileage and vehicle history, can tell what's really going on.

Get a diagnostic for YOUR car

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Meca doesn't replace an in-person check by a professional. For any serious sign (a flashing light, a major loss of power, a fuel smell), see a mechanic promptly.

Frequently asked questions

Will the car still start?

Usually yes, thanks to the module's fallback mode, but driving will feel less smooth than normal.

Should wiring be checked before replacing the sensor?

That's a good idea — a loose connector or damaged wiring is cheaper to fix than a sensor, and causes the exact same code.

Is this different from P0101?

Yes: P0101 covers a signal that's out of range but present, P0102 covers a signal that's implausibly low or flatly absent.