Infiniti P1128 Manifold Absolute Pressure Sensor Signal Lower Than Expected

Description

Possible causes
– Engine mechanical condition
– Faulty Manifold Absolute Pressure (MAP) sensor
– Manifold Absolute Pressure (MAP) sensor harness is open or shorted
– Manifold Absolute Pressure (MAP) sensor circuit poor electrical connection
Symptoms
– Engine Light ON (or Service Engine Soon Warning Light)
P1128 Infiniti ACURA OBD Code Description

The Manifold Absolute Pressure (MAP) sensor senses manifold absolute pressure (vacuum) and converts it into electrical signals. The MAP sensor outputs low signal voltage at high-vacuum (idling) and high signal voltage at low-vacuum (throttle valve wide open).

The engine control module (ECM) compares a predetermined MAP value at a given throttle position and manifold absolute pressure to the output voltage value of the MAP sensor.

If the MAP sensor outputs lower voltage than expected, the ECM detects a malfunction and stores a DTC.


The OBD2 Code Information Be Applicable For Infiniti:

,2013 Infiniti M35h GT,2013 Infiniti JX,2013 Infiniti FX,2011 Infiniti QX,2011 Infiniti M35h,2011 Infiniti M,2011 Infiniti JX Concept,2011 Infiniti IPL G Coupe,2011 Infiniti EX30d,2009 Infiniti G37,2009 Infiniti FX50,2009 Infiniti FX37,2009 Infiniti FX35,2009 Infiniti Essence Concept,2009 Infiniti EX37,2008 Infiniti QX56,2008 Infiniti M45x,2008 Infiniti M45s,2008 Infiniti G37 Coupe,2008 Infiniti EX35,2007 Infiniti G35 Sedan,2007 Infiniti EX Concept,2006 Infiniti QX56,2006 Infiniti Q45,2006 Infiniti M45,2006 Infiniti M35x,2006 Infiniti M35,2006 Infiniti FX45,2005 Infiniti Q45,2005 Infiniti G35,2005 Infiniti FX45,2004 Infiniti QX56,2004 Infiniti M45 Concept,2004 Infiniti I35,2003 Infiniti QX4,2003 Infiniti Q45,2003 Infiniti M45,2003 Infiniti I35,2003 Infiniti G35,2003 Infiniti FX45,2003 Infiniti FX35

 

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