Author Topic: negative boost psi with engine off  (Read 5548 times)

Offline jpolito

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negative boost psi with engine off
« on: December 10, 2012, 08:17:00 PM »
Good evening all, just wondering if anyone else has experienced something similar with their devices?

Not sure why this would be happening.


Car: 2011 Sonata Turbo

Offline UltraGauge Admin

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Re: negative boost psi with engine off
« Reply #1 on: December 31, 2012, 09:53:03 AM »

If your vehicle has a barometric pressure gauge, then UG will adapt for changes in atmospheric pressure.  If not, then UG assumes sea level pressure.
Also, there are two sensors involved, the barometric pressure sensor and the engine's MAP sensor.  Due to inherent inaccuracies in these sensors, they will likely not agree exactly and a positive or negative value of Boost will be displayed with the engine not running.