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MAP vs Barometric pressure check

jg45

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John
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2020 JLUR Recon
Anyone with JScan that can check what their intake manifold absolute pressure and absolute barometric pressure reads in psi with key on/engine off?
My understanding is they should be the same when the engine is off, but my intake MAP is reading 9psi and Barometric is reading 15psi. This picture are the two PIDs I am comparing .

Jeep Wrangler JL MAP vs Barometric  pressure check Screenshot_20240314-222009
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jg45

jg45

Well-Known Member
First Name
John
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Location
Bartlett, TN
Vehicle(s)
2020 JLUR Recon
Anyone out there that can compare these two readings with key on/engine off. Everything I read online says that the map should read the same as barometric with the engine off. Mine is reading several PSI lower which has me wondering if that is causing a lean condition until the engine is warm enough to go into closed loop.
I also found out that what most online resources show as the MAP sensor (just upstream from the throttle body) is the boost pressure monitor. What is reported in software as the MAP is the T/Map that is downstream of the throttle body.
 
 







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