Problems of the mass airflow sensor: symptoms, cost and affected models
We have documented 10 faults of the mass airflow sensor in 10 engines, affecting 61 models of car in our database. The most important by severity and frequency: VP44 injection pump and air mass meter failure (2.0 DTI and 2.2 DTI), mass air flow sensor failure (M111) and air mass meter (MAF sensor) failure (1.8 T 20v). At an independent garage, the repair costs from €100 to €300 depending on the engine or car.[1]
How it works and why it fails
Mass airflow sensor
The mass airflow sensor measures the air entering the engine so the ECU can work out how much fuel to inject. If it gets dirty or fails, the engine receives the wrong mixture: it loses power, stutters or emits smoke, especially on diesels.
What to do
The symptoms are easily confused with those of an intake air leak or a faulty turbo, so read live data with diagnostic equipment before replacing it. A badly fitted air filter, or one soaked in oil, shortens its life.
General explanation by MotorFiable. The specific faults of each engine and car, with their sources, are on the linked pages.
Common symptoms
The symptoms that come up most often in the documented faults of the mass airflow sensor. Open each one to see what other faults cause it.
Problems of the mass airflow sensor by engine
From most to least important (severity × frequency). Each page details the affected versions and years, symptoms, cost and how to check for it.
- 1High severityFrequency: Occasional2.0 DTI and 2.2 DTIVP44 injection pump and air mass meter failureGerman Wikipedia documents recurring failures of the Bosch VP44 injection pump and the air mass meter in the early years of this engine. An owner testimony for this engine describes the pump being replaced at 192,500 km, at a cost the owner calls «prohibitive».
- 2Low severityFrequency: CommonM111Mass air flow sensor failureYes: the M111 mass air flow sensor can fail with use and cause jerking or rough running. English-language Wikipedia documents it on the W210 E-Class, and a French owner survey of the SLK R170 names it as the most-cited fault on that model.
- 3Low severityFrequency: Common1.8 T 20vAir mass meter (MAF sensor) failureThe air mass meter (MAF sensor) fails fairly often on the 1.8T: on the 150 hp Audi A3 it appears in 3 of the 11 reports collected, and it is also documented on the 180 and 225 hp Audi TT. It causes hesitation and loss of power; it is fixed by replacing the sensor.
- 4Low severityFrequency: Common1.9 TDIDirty or faulty air flow meter on the 1.9 TDI (loss of power)The air flow meter is a known weak point of the 1.9 TDI: it gets dirty or gives wrong readings, and the control unit limits the engine, causing a sudden loss of power. It is cheap to fix and does not damage the engine.Repair (garage): €100–€300
- 5Low severityFrequency: OccasionalBMW M47Faulty air flow meter on the BMW M47 (loss of power)On the 2.0 M47 diesel the air flow meter appears among parts that can fail with age and cause loss of power or judder. It is fixed by replacing the sensor; other causes must be ruled out first.Repair (garage): €100–€300
- 6Low severityFrequency: OccasionalBMW M57Faulty air flow meter on the BMW M57 (loss of power)The air flow meter is a known fault on six-cylinder M57 diesels: over time it loses accuracy and the car pulls less. It is a cheap repair compared with the turbo or injection.Repair (garage): €100–€300
- 7Low severityFrequency: Occasional1.9 JTD/Multijet and 2.4 JTDFaulty air flow meter on the 1.9 JTD / Multijet (loss of power)On the 1.9 JTD and 1.9 CDTI the air flow meter repeatedly appears among ancillary faults: loss of power. It is fixed by replacing the sensor after ruling out air leaks and the EGR.Repair (garage): €100–€300
- 8Low severityFrequency: Occasional1.4, 1.6 and 1.8 VVT-iAir mass meter and lambda sensor failuresOn a minority of Corolla, Avensis and Corolla Verso cars with this engine, the air mass meter (MAF sensor) or the lambda sensor gives wrong readings and lights up the engine warning light; it is a relatively simple repair and does not compromise the engine.
- 9Low severityFrequency: Rare2.2 CDI (OM646)Faulty air flow meter on the 220 CDI (OM 611 and OM 646)On the 220 CDI the air flow meter fails in a minority of units: 14 of the 503 opinions collected by fiches-auto. It alters the air/fuel mixture and is cheap to repair.Repair (garage): €100–€300
- 10Low severityFrequency: Rare2.2/2.5 dCiDirty or misreading mass airflow sensorThe 2.2 dCi's mass airflow sensor can get dirty and give incorrect readings; the Almera reliability report points to it as a known problem of the engine, although with few recorded cases.
Engines with faults of the mass airflow sensor
Problems of the mass airflow sensor by make
Problems of the mass airflow sensor in your car
15 cars have several documented faults of the mass airflow sensor. Choose yours to see only the ones that affect them, by engine and by year.
Audi 2
Mercedes-Benz 1
Volkswagen 2
How much it costs to repair a fault of the mass airflow sensor
Sorted from the most expensive repair to the cheapest. Prices in Spain including VAT (parts and labour); what each figure includes is on its page.
- Garage
- €100–€300
- Dealer
- No data
- Published figure[1]
- Garage
- €100–€300
- Dealer
- No data
- Published figure[1]
- Garage
- €100–€300
- Dealer
- No data
- Published figure[1]
- Faulty air flow meter on the 1.9 JTD / Multijet (loss of power)
1.9 JTD/Multijet and 2.4 JTDLow severity
- Garage
- €100–€300
- Dealer
- No data
- Published figure[1]
- Garage
- €100–€300
- Dealer
- No data
- Published figure[1]
How we calculate costs · The most expensive repairs across all engines
Frequently asked questions
Which engines have the most faults of the mass airflow sensor?
By severity and frequency, the 2.0 DTI and 2.2 DTI (VP44 injection pump and air mass meter failure, high severity), the M111 (mass air flow sensor failure, low severity), the 1.8 T 20v (air mass meter (MAF sensor) failure, low severity), the 1.9 TDI (dirty or faulty air flow meter on the 1.9 TDI (loss of power), low severity), the BMW M47 (faulty air flow meter on the BMW M47 (loss of power), low severity) and the BMW M57 (faulty air flow meter on the BMW M57 (loss of power), low severity). In total we have documented 10 engines with faults of the mass airflow sensor.
How much does it cost to repair a fault of the mass airflow sensor?
It depends a lot on the engine or car. At an independent garage, from €100 to €300, including VAT, based on the 5 faults with a documented cost. The most expensive is dirty or faulty air flow meter on the 1.9 TDI (loss of power) (1.9 TDI).
What symptoms does a fault of the mass airflow sensor cause?
The most frequently cited in the documented faults: gradual loss of power, jerking or juddering when accelerating, engine fault warning light (check engine), hard starting or engine will not start, engine stalls or cuts out while driving and sudden loss of power (limp mode).
Sources
Every fact on this page links to its source. If you find an error, let us know.
- Caudalímetro o sensor MAF: qué es, cómo funciona y cuáles son las averías más frecuentesDiariomotor · Motoring press · consulted 30 October 2026 · in Spanish