The advent of the autonomous car has highlighted the fundamental importance of having good sensors. That being said, we have long been committed to providing effective – and reliable – sensors to our customers. So whether you are looking for engine and transmission sensors, or for comfort and safety – not to mention emissions and e-mobility – you should definitely take a look at our range.
Located on the intake hose – upstream of the throttle body and downstream of the air filter – the mass air flow sensor is responsible for measuring the quantity and temperature of air absorbed for engine combustion, before transmitting all this data to the ECU. This sensor also determines the rate of exhaust gas recirculation (and therefore the opening of the EGR valve).
The data provided by the mass air flow sensor, crossed with that from other sensors (crankshaft sensor, oxygen sensor, DPF sensor, etc.), enables the ECU to optimise the fuel injection parameters, leading to a reduction in consumption necessary to comply with European anti-pollution standards and to limit the formation of smoke during transient phases.
The mass air flow sensor consists of a plastic tube with 2 sensors inside, or more precisely a mass air flow sensor and an air temperature probe. Thus, the combination of these two sensors allows the necessary information to be transmitted to the computer.
SYMPTOMS
The following symptoms are often associated with mass air flow sensor failure:
DIAGNOSIS PROCEDURE
First and foremost, you need to visually inspect the mass air flow sensor to determine if it has a clear fault that can explain its failure. It is strongly recommended to check for the following:
Secondly, you can check whether the mass air flow sensor works correctly by identifying the wire that transmits the information to the ECU. Once identified, start your vehicle – the voltage displayed corresponds to the air flow rate required by the engine at its idle speed. Then check that the voltage increases when you accelerate and decreases when you decelerate.
If the previous tests are not conclusive, you must replace your vehicle’s mass air flow sensor.
CAUSES OF FAILURE
Constantly subjected to the rough engine environment, a mass air flow sensor may fail due to:
INSTALLATION INSTRUCTIONS
To ensure a quick and efficient installation, you must refer to the following instructions:
INSTALLATION TIPS
As the mass air flow sensor is essential to the correct operation of the engine, it is important to follow a certain number of recommendations when replacing it:
PREVENTIVE INFORMATION
The above items are provided for information purposes only. They do not replace the advice of a qualified technician or mechanic. We strongly recommend that you consult a professional if you are unsure of what to do. Otherwise, we cannot accept responsibility for any damage to your vehicle.
When a mass air flow sensor fails, the engine fault signal (amber coloured) lights up on the dashboard. Your vehicle’s fuel consumption will increase, and so will its pollutant emissions. So, do not be surprised if you see black smoke coming from your exhaust. Without the right information, your ECU will no longer be able to manage the stoichiomletric mixture correctly, resulting in frequent stalling – or even an inability to start.
First of all, we strongly recommend that you visually check the mass air flow sensor; i.e., the wiring (whether there are burnt, damaged, corroded or deteriorated wires), the fuses and the electrical connections (damaged, dirty and/or oxidised pins).
Secondly, using a multimeter, you can check that the mass air flow sensor is working properly by verifying the presence of an electrical current at the connector output. Once you have identified the wire transmitting the information to the ECU, start your vehicle – the voltage displayed corresponds to the air flow required by the engine at idle speed. Then check that the voltage increases when you accelerate and decreases when you decelerate.
If the above tests are not conclusive, you need to replace your vehicle’s mass air flow sensor.
Although automotive sensors are built to a very high standard, they do not last forever and there are a number of reasons why they may need to be replaced, including mechanical damage – due to an accident, or sustained vibration. Furthermore, the mass air flow sensor is located in a particularly rough engine environment, and dirt and/or excessive humidity can lead to clogging or blocked intake (from the turbo, EGR valve or oil vapour recirculation).
We recommend the following steps to replace your mass air flow sensor as efficiently as possible and to limit possible mistakes:
As a sensor specialist, we recommend the following to extend your mass air flow sensor’s durability:
