Firebird V8-350 5.7L VIN P SFI (1996)
Manifold Pressure/Vacuum Sensor: Description and Operation
The Manifold Absolute Pressure (MAP) sensor responds to changes in the intake manifold pressure. The pressure changes as a result of engine
load and speed. The map sensor converts this to a voltage output.
A closed throttle on engine coast down would produce a relatively low map output voltage. A wide open throttle would produce a high map output
voltage. This high output voltage is produced because the pressure inside the manifold is the same as outside the manifold. The MAP is inversely
proportional to what is measured on a vacuum gage. The MAP sensor is used for the following:
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Altitude determination.
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Ignition timing control.
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EGR diagnostic.
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Speed density fuel management default.
When the PCM detects a malfunction in the MAP sensor circuit, the following DTCs will set:
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DTC P01O6 circuit performance malfunction.
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DTC P01O7 circuit low.
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DTC P01O8 circuit high.
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DTC P11O7 intermittent circuit low.
LEGEND
(1) Electrical Connector
(2) Manifold Absolute Pressure (MAP) Sensor
