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Differential Pressure Readings at Idle

 
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flightmaster
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Post14-01-2012, 0:09    Subject: Differential Pressure Readings at Idle Quote

Hello,

I recently read the differential pressure values at idle, and it was 2.55.

The offset is: 0.0.

When you gently press the accelerator pedal while the vehicle is stationary, the reading immediately jumps to 5.1.


Are these values okay?


With the engine off, both readings are 0.0, which is fine.


Can we conclude from this that the differential pressure sensor is working correctly?

Thank you in advance.


Translated on 06-09-2026, 22:32.
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Stummel
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Post14-01-2012, 20:55    Subject: Differential Pressure Readings at Idle Quote

Hi there.


It's right there, specifying what the target values should be...


'According to the specifications, the vacuum pressure should be around 5 mbar when idling, and it's understandable that it goes above that immediately, especially if the filter is still relatively full.'


What surprised me about the BMN (presumably a pressure sensor) is that it's currently showing 3 mbar with the engine idling! The offset was -5.1 mbar.


What does the offset value indicate? And regarding the 3 mbar... is the sensor faulty?


Translated on 06-09-2026, 22:34.
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