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Mass Airflow Sensor Operation The Mass Airflow (MAF) sensor directly measures the mass of air being drawn into the engine. The sensor output is used to calculate injector pulse width. The (MAF) sensor is what is referred to as a "hot-wire sensor". The sensor uses a thin platinum wire filament, wound on a ceramic bobbin and coated with glass, that is heated to 200*C (417*F) above the ambient air temperature and subjected to the intake airflow stream. A "cold-wire" is used inside the (MAF) sensor to determine the ambient air temperature. Battery voltage from the EEC power relay, and a reference signal and a ground signal from the PCM are supplies to the (MAF) sensor. The sensor returns a signal proportionate to the current flow required to keep the "hot-wire" at the required temperature. The increased airflow across the "hot-wire" acts as a cooling fan, lowering the resistance and requiring more current to maintain the temperature of the wire. The increased current is measured by the voltage in the circuit, as current increases, voltage increases. As the airflow increases the signal return voltage of a normally operating (MAF) sensor will increase. Testing 1. Using a multimeter, check for voltage by back probing the (MAF) sensor connector. 2. With the key ON, and the engine OFF, verify that there is at least 10.5 volts between the VPWR and GND terminals of the (MAF) sensor connector. If voltage is not within specification, check power and ground circuits and repair as necessary. 3. With the key ON, and the engine ON, verify that there is at least 4.5 volts between the SIG and GND terminals of the (MAF) sensor connector. If voltage is not within specification, check power and ground circuits and repair as necessary. 4. With the key ON, and the engine ON, check voltage between GND and SIG RTN terminals. Voltage should be approximately 0.34-1.96 volts. If voltage is not within specification, the sensor may be faulty. Removal & Installation (4.6L & 5.4L) 1. Disconnect the negative battery cable. 2. Release the air cleaner clamp and separate the air cleaner halves. 3. Remove the grommet from the air cleaner housing and slide the grommet down the hardness. 4. Remove the (MAF) sensor plate and (MAF) sensor from the air cleaner. 5. Detach the (MAF) sensor from the harness. 6. Remove the retaining nuts and remove the (MAF) sensor. 7. Installation is the reverse of removal.
Marley Williamson
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Where is the Mass Air Flow sensor located on a 2003 Ford expedition?
In your air box at the filter side
Where is the mass air flow Sensor on a 2001 ford expedition 4.6l engine?
On a 2001 Ford Expedition , 4.6 : The Mass Air Flow sensor is between the engine air filter and the large diameter engine air intake tube * it is INSIDE the round shaped plastic housing
Where's the mass air flow sensor located on a ford expedition 2003?
On a 2003 Ford Expedition : The Mass Air Flow Sensor is between the engine air filter and the big engine air intake tube . If it's the same as on my Ford Explorer it is INSIDE a circular shaped plastic housing ( you can see where the wires enter the housing )
Where is the mass air flow sensor on a 1999 ford expidition?
On a 1999 Ford Expedition : The Mass Air Flow Sensor is located INSIDE the round shaped plastic housing , between the engine air filter housing and the engine air intake tube
Where is the mass air flow sensor located on a 2000 ford expedition?
Air intake hose between tb and air cleaner
Where is mass airflow sensor located on 1999 expedition?
On a 1999 Ford Expedition : The Mass Air Flow sensor is between the engine air filter and the large diameter engine air intake tube ( it is INSIDE a round shaped plastic housing )
Where is mass air flow sensor located on Ford Fusion?
where is mass air flow sensor located at on a 2011 ford fusion 4 cylinder
Were is the MAF sensor located on 97 ford expedition?
On a 1997 Ford Expedition : The Mass Air Flow sensor is between the engine air filter and the big engine air intake tube ( it is INSIDE the round plastic housing but you will see where the wires go in )
How does the maf sensor look on a 1997 Ford Expedition?
On a 1997 Ford Expedition : The Mass Air Flow sensor is between the engine air filter and the big rubber engine air intake tube ( it is INSIDE a circular shaped plastic housing , you will see where the wires go inside )
How do you clean the mass air flow sensor on a 2003 expedition?
you will almost always have to replace them.
Where is the mass air flow - MAF - sensor relay located on 1992 Ford Explorer?
The Mass Air Flow sensor is located on top of the air filter housing on Ford Explorer.
Where airflow sensor locate in 98 Ford Expedition?
On a 1998 Ford Expedition : The Mass Air Flow sensor is located between the engine air filter and the big rubber engine air intake tube ( it is INSIDE the circular shaped plastic housing , you will see where the wires go inside )
