Inlet Air Pressure Sensor (Service Code 12)
Pg : Vacuum (gauge) of Throttle Assy
Pl : Local Atmospheric Pressure (absolute) measured by a barometer
Pv : Vacuum (absolute) of Throttle Assy
Vv : Sensor Output Voltage (v)
Pv = Pl – Pg
For example, suppose the following data is obtained in the chart of the next page.
Pg = 8 cmHg (vacuum gauge reading)
Pl = 70 cmHg (barometer reading)
Vv = 3.2 V (digital volt meter reading)
Pv = 70 – 8 = 62 cmHg (abs)
Plot this Pv (62 cmHg) at a point  on the chart and draw a vertical line through the point. Then, you
can get the usable range  of the sensor output voltage.
Usable range = 3.04
Plot Vv (3.2 V) on the vertical line. → Point .
Results: In the chart, Vv is within the usable range and the sensor is normal.
Pv = 24
55 cm Hg
FUEL SYSTEM (DFI) 3-51