Boost/Vac Readings way off

Silverstar

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Alrighty, I posted a thread on NASIOC...and well frankly I didn't get much help from them in the past week about it, so I pose this question to my good friends here.

This is at idle,


Foot resting on pedal to ensure that it is reading


This is after being in for the transmission work, and really noticed this the night after I got it back. During all the work my intercooler, downpipe, and a couple other various parts came off.

If I remember correctly, I should be pulling 18-20inHG idle. And I am also getting only 11PSI under WOT, tested it in 3rd and 4th to be sure. This is beyond me so I have some questions.

1. Is 30inHG possible?
2. Could the dealer have re-installed the parts improperly to cause this?
or..
3. Could cold temperatures be causing this?

Hoping I can figure something out before I go to either my dealer or Prosport to order another sensor.
 
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Dogbert

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I would say re-check your sensor with an eagle eye. What were the couple other various parts that came off?
 

Spectre

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A backfire that blew off parts can cause severe damage to pressure sensors.
 

Silverstar

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Also, I've checked all lines and they look fine, vacuum hose coming off of the BPV is not kinked or damaged, line going to sensor isn't kinked and looks to be making a good seal on the connections, being reverse flare connections I'd hope they are :mrgreen:

I would say re-check your sensor with an eagle eye. What were the couple other various parts that came off?
Driveshaft, heatshields, skidplate. Took the sensor off and apart and it didn't seem to have anything wacky going on in there, there was maybe some small particles on the diaphragm part, but nothing like punctures or knicks.
A backfire that blew off parts can cause severe damage to pressure sensors.
Backfire? I'm confused. I guess I need to rephrase my parts comment :D, those are parts I saw that were removed during the transmission work. It was warranty work done at the Subaru dealer.
 
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Nocturnal

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I can't see the cold temps affecting this, so I'd rule that out. Potentially a dicky actuator? I'd check where the sender for the gauge is plumbed in too.
 
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