P0100 - Mass Air Flow (MAF) Circuit Malfunction
Basically this means that there is a problem with the Mass Air Flow (MAF) sensor or circuit. Other MAF sensor circuit DTC trouble codes are P0101, P0102, P0103, and P0104.
You will likely not notice any serious drivability problems, although there may be symptoms such as a general decrease in power or sluggishness.
Causes: A code P0100 may mean that one or more of the following has happened:
* The MAF may be disconnected, or a wiring connection may be bad
* The MAF sensor may be faulty
Possible Solutions: The simplest thing to do is to reset the code and see if it comes back. Then start with the cheapest, easiest repair procedures:
* Verify that the Mass Air Flow Sensor wiring is connected properly and that there are no broken / frayed wires.
* Unplug and reconnect the MAF wiring harness
* Check the voltage of the MAF sensor (refer to a repair manual for vehicle specific information)
* Replace the MAF sensor
Then, like a reference guide check this TSB DTC P0102 MAF
and this article about Mass Air Flow sensor, what does it do and how it does it
Test, check it and keep us updated.