Air flow meter is used to measure the flow of air or water through a tube. Automobiles use air flow meter to measure the air quantity entering the engine at a given time and to ensure smooth functioning of the engine.
Air flow meters have various important functions some of which are listed below.
Speed Regulation of Air Flow: These are used to regulate the flow of air or gas present in the tube and to measure the speed of the flow.
To Compute Consumption: These equipments can be used to measure the gas consumption in the tube apart from the rate of flow of gas through the tube.
To Guide the Drivers: The air flow meters are usually connected to the computers, which indicate normal readings. In the event of an abnormal rise or dip in the flow or during equipment malfunctions, warning lights are flashed to alert the drivers. The meters also give vital information relating to the functions of the engines.
It Serves as a Regulator: Digital air flow meter equipment can also be used as to regulate the flow of air through the adjustments of the valves.
As air flow meter plays an important role in regulating the flow of air and the functions of the engine, it is important that these equipments should be maintained properly. Here are some tips on how to diagnose a faulty air flow meter.
Check Engine Light: One of the earliest symptoms of a faulty mass air flow meter (MAF) is the flashing light on the check engine light on the instrument panel. This warning light could be triggered due to various functions and to ascertain whether it is due to any problems of the mass air flow meter, the cars computer has to be analyzed carefully. An auto mechanic can get the cars computer analyzed. The car owners too can do it using a digital auto diagnostics scanner, which is available in any auto spare part stores. If the scanner codes refer to a malfunctioning MAF, the MAF should be replaced.
Low Performance of the Engine: As the MAF is responsible to maintain a proper balance of air and fuel inside the engine, any failure in this gadget can result in a range of engine performance problems including low gas mileage, stalling or knocking among others.
Measure the Hot Wire MAF Sensor's Output Voltage. Typically a voltmeter attached to the MAF sensor should read around 2.5 volts. Raise the rpm of the engine and take the voltmeter readings. It should register a steady increase in the reading corresponding to the throttle opening. If the voltage readings are erroneous, that could mean that the sensor is not producing signals.
Check the Self-cleaning Circuit Relay on MAF Sensor. The self cleaning circuit cleans the MAF wire. If the relay that regulates the current to the circuit is broken, then the computer will be unable to clean the wire. The dirt and other debris could leave the sensor faulty.
Once the cause of the MAF malfunction is identified, it should be rectified immediately to restore the normal functioning of the air flow meter.