Boost issues

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Tigerofindy

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When at idle, my boost gauge is far left. When accelerating, it gets slightly above 0 and if I try to push it, i may get to 8-10psi. Its been doing this for about a week. Anyone else have this isdie? Trying to resolve without the dealership headache.

No engine lights or warnings have popped up yet either.
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Littlefx4

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Sounds normal to me. As long as there’s no significant increase in engine speed & load, that gauge will stay to the left. These trucks, along with most modern FI manufactured vehicles, have very conservative tunes in order to increase longevity.

Drop it in Sports mode; play around a little & feel the difference.
 

FordTechOne

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I agree it sounds like normal operation, but you said it’s only been doing it a week? How was it before? Any mods?
 

Swacer_2

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Is this your first turbo vehicle? If so, what you're seeing is on the left hand side of the gauge is vacuum, aka, wastegate. If you aren't on the gas, or imparting a load on the engine requiring boost, your wastegate will be open (anywhere from fully where the bar is fully to the left to almost closed where the bar is straight up). Once you start making boost, the wastegate will close and you will start making positive pressure aka boost.

You can be making 10psi boost with your foot on the gas, and the moment you let off, the wastegate is going to open and its going to go full vacuum. You definitely want it to work that way. Imagine having an air tunnel, and the only way out is an open door (intake) while a second door is shut (waste gate). If you slam that first door shut, that air HAS to go somewhere, so the second door opens to allow the system to dump that access air.

The boost pressure you're seeing is fine, I typically see 2-7psi during my normal drives. I only see 10psi or so at highway speed climbing a hill in 10th gear.
 

GTTXRAP

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I started to notice this on my 37 when I took delivery and asked service mgr who said completely normal.
 
OP
OP
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Tigerofindy

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Is this your first turbo vehicle? If so, what you're seeing is on the left hand side of the gauge is vacuum, aka, wastegate. If you aren't on the gas, or imparting a load on the engine requiring boost, your wastegate will be open (anywhere from fully where the bar is fully to the left to almost closed where the bar is straight up). Once you start making boost, the wastegate will close and you will start making positive pressure aka boost.

You can be making 10psi boost with your foot on the gas, and the moment you let off, the wastegate is going to open and its going to go full vacuum. You definitely want it to work that way. Imagine having an air tunnel, and the only way out is an open door (intake) while a second door is shut (waste gate). If you slam that first door shut, that air HAS to go somewhere, so the second door opens to allow the system to dump that access air.

The boost pressure you're seeing is fine, I typically see 2-7psi during my normal drives. I only see 10psi or so at highway speed climbing a hill in 10th gear.
First turbo vehicle and learning the difference. I can turn a wrench but far from the technical details. Much to learn.
 

BoostCreep

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Is this your first turbo vehicle? If so, what you're seeing is on the left hand side of the gauge is vacuum, aka, wastegate. If you aren't on the gas, or imparting a load on the engine requiring boost, your wastegate will be open (anywhere from fully where the bar is fully to the left to almost closed where the bar is straight up). Once you start making boost, the wastegate will close and you will start making positive pressure aka boost.

You can be making 10psi boost with your foot on the gas, and the moment you let off, the wastegate is going to open and its going to go full vacuum. You definitely want it to work that way. Imagine having an air tunnel, and the only way out is an open door (intake) while a second door is shut (waste gate). If you slam that first door shut, that air HAS to go somewhere, so the second door opens to allow the system to dump that access air.

The boost pressure you're seeing is fine, I typically see 2-7psi during my normal drives. I only see 10psi or so at highway speed climbing a hill in 10th gear.
This is not at all how a wastegate functions. At idle and low boost, the wastegate is always shut. Once you hit your wastegate spring pressure (or electronic boost threshold in the case of the Raptor with an electric wastegate), then the wastegate opens in order to control boost at higher loads and rpm’s in order to avoid overboosting or boost creep. When the motor is in vacuum, and boost pressure less than 10psi, the wastegate will be closed. Not sure what pressure it opens on this truck but I would assume somewhere in the neighborhood of 1 atm (14.7psi) or a little less. At peak boost the wastegate will be fully open.

OP, your operation sounds normal most likely. Put it in sport mode and go WOT going up a slight incline, letting it rev out. If you don’t see higher boost under that condition, something is wrong.
 
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