Pressure Sensor

Courtesy of VOLVO CARS CORPORATION

1. MAP (Manifold Absolute Pressure)
2. TMAP (Temperature Manifold Absolute Pressure)
3. CMAP (Compressor Manifold Air Pressure)

MAP (Manifold Absolute Pressure), intake manifold

The sensor contains a Piezo sensor (pressure) which, amongst other things, is used for the following:

• to calculate the flow in the engine, via the volumetric efficiency.
• to calculate the adaptation of the volumetric efficiency to request correct boost pressure levels.
• to estimate the stored mass in the intake manifold's volume, via the pressure, to thereby calculate the flow in the intake system.

TMAP (Temperature Manifold Absolute Pressure), ahead of the throttle ETM

The sensor contains a Piezo sensor (pressure) and NTC sensor (temperature) used for:

• adjustment of boost pressure.
• calculating the flow through the throttle ETA via pressure and temperature.
• calculating estimated stored mass in the charge air cooler's volume, which means that the flow in the intake system can be calculated.
• calculating the pressure in the manifold.
• using the actual temperature, calculate the engine's efficiency.

CMAP (Compressor Manifold Air Pressure), after compressor, engines B4204T9/T10

Is a Piezo sensor (pressure), which is used for:

• adjustment of the compressor's boost pressure.
• calculating the stored mass in the pressurized compressor volume.