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Manifold pressure reading under boost

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Installed a line from my intake manifold plenum to my MAP sensor located on my standalone ECU. It reads atmospheric KPA roughly around 96 kPa (depending on elevation). I installed a base map with adjustments based off of new hardware on my ECU and started it up. During idle my MAP sensor reads around 32~ kPA which seems extremely low considering I have a turbo charged system.

According to the tuning guides / videos from HP Academy, tuning above 100kpa is roughly around the early-mid boost region. During idle, I believe I should have a MAP reading of 96 kPa or higher?

Furthermore, searching around the internet, it seems like having low manifold pressure is normal but all the tuning guides from HP Academy (including the free ones on YouTube) work with excess of 100 kPa or beyond for tuning.

So did I install my MAP sensor incorrectly? (even though everyone says I should install the line on the plenum)

Why is my MAP reading so low? (when this should be at atmospheric or higher)

Attached Files

The key word there is "idle". A little thought will result in the "doh" moment... hint, reducing cylinder filling to minimise torque under low, or no, engine load and the position of the throttle body.

Hi Dannysilvia,

Your idle MAP values of 34Kpa are fine with engine on and idling. Did you calibrated the internal map sensor on EMU configuration ?

You should adjust the internal MAP and BARO offsets to match your atmospheric pressure with engine off. Go to Sensors Setup>MAP Sensor , adjust the offsets while checking tune display until they match your real atmospheric pressure (use a weather app to get the values for your location)

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