Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

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LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

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Manifold Pressure/Vacuum Sensor: Testing and Inspection

A Tech 1 scan tool displays manifold pressure in kPa and Manifold Absolute Pressure (MAP) sensor signal voltage. Low pressure (high vacuum) displays a low voltage while a high pressure (low vacuum) displays a high voltage. A fault in the MAP sensor circuit should set a Diagnostic Trouble Code (DTC) 33 or 34. A DTC 33 or 34 may set if a rough or unstable idle exists. Chart C-1D Manifold Absolute Pressure (MAP) Output Check can also be used to check the MAP sensor. Testing and Inspection