Circuit Description

The powertrain control module (PCM) uses the following readings in order to calculate the predicted mass air flow (MAF) rate:

• The throttle position (TP)
• The barometric (BARO) pressure
• The intake air temperature (IAT)
• The engine revolutions per minute (RPM)

The PCM compares the predicted MAF value to the actual MAF value, and to the speed density calculation in order to verify the proper throttle operation.