P0102 means the mass air flow sensor is reporting a voltage or frequency below the expected idle minimum. The ECU thinks almost no air is entering the engine, so it cuts fuel injection accordingly. The root cause is usually a contaminated MAF element, a major air leak after the sensor, or a wiring fault.
P0102 means the mass air flow sensor is reporting a voltage or frequency below the expected idle minimum. The ECU thinks almost no air is entering the engine, so it cuts fuel injection accordingly. The root cause is usually a contaminated MAF element, a major air leak after the sensor, or a wiring fault.
P0102 is a fuel system-related diagnostic trouble code classified as moderate severity. When your vehicle's ECU detects this condition, it stores P0102 and illuminates the check engine light.
If your vehicle has triggered P0102, you may notice one or more of these symptoms:
Here are the most common causes of P0102, ranked by how likely they are to be the culprit:
Generally yes, for short-term driving. Driveable but the engine will run poorly. With abnormally low MAF readings, the ECU under-fuels the engine, causing lean conditions, hesitation, and possible stalling. Safe to drive to a shop, but long-term lean running can damage catalysts and valves.
Follow these steps to pinpoint the root cause of P0102:
Repair costs for P0102 vary depending on the root cause and your vehicle. Here are typical estimates:
Prices estimated as of March 2026. Costs vary by region, vehicle, and shop.
P0102 behaves differently depending on your vehicle. Select your car below for model-specific causes, known issues, and adjusted cost estimates:
Nissan Qashqai
See Nissan-specific causes & costBMW 3 Series
See BMW-specific causes & costVolkswagen Golf
See Volkswagen-specific causes & costAudi A4
See Audi-specific causes & costFord Focus
See Ford-specific causes & costThese codes are often seen alongside P0102 or indicate related issues:
Yes, short distances. The engine runs lean and rough because the ECU under-fuels based on the low MAF signal. Long-term lean running damages catalytic converters and exhaust valves, so plan the repair within a week.
Often yes. Around half of P0102 cases are resolved by a proper clean with MAF-specific cleaner. Never touch the sensing element with anything, and never use brake or carb cleaner since they leave residue that destroys the hot-wire.
Three common reasons. First, residue from the wrong cleaner contaminated the element. Second, the sensor was already failing and cleaning revealed the underlying fault. Third, the air filter or intake boot was not reseated correctly, creating a new air leak. Inspect all three before replacing the sensor.
Typically 150,000–250,000 km on petrol engines if the air filter is changed regularly. Diesel MAF sensors tend to last longer (less contamination from PCV blow-by). BMW N52/N54/N55 and Audi 2.0 TFSI MAF sensors are well-known early failures, often before 120,000 km, especially with aftermarket oiled air filters.
P0101 repair often costs under €15: cleaning the MAF sensor fixes about half of cases. If that fails, replacement runs €70 to €380. Step-by-step fix guide.
The Reduced Engine Power message is the ECU cutting throttle to protect itself. Here is what triggers it, whether you can drive, and what the fix costs.
Clean your MAF sensor in 15 minutes for under €10. Step-by-step guide with OBD2 verification to fix hesitation, rough idle, and poor fuel economy.
Your car logged P0102. Skanyx reads it on any standard Bluetooth OBD2 adapter, tells you whether it is safe to keep driving, and shows the €8-€350 repair range so you know the number before a shop quotes you.
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