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Odd mpg & boost limit issue

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Location
Kansas City
#1
2015, 35k miles, Stage 3, e-tuned, zero issues since new. My weekly driving route rarely varies and my driving style is always the same/sane.

I used to run a 93 tune, max boost psi 24.5ish & avg 31mpg in mixed driving

I currently am running a 91 tune, max boost 24.5ish & avg 32 in mixed driving. Low boost slot limits boost to 10ish boost psi.

Every once in a while my boost is capped at 15.5ish psi and subsequently my mpg falls to around 17mpg. Cycling between slots doesn't correct the issue nor does restarting the engine. No boost leaks or any other issue to be discovered.

Any thought? TIA
 


WeTheNorth

1000 Post Club
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#2
Hey,

I would start by asking your tuner, as a diy, you could try and uninstall and reinstall your AP? Just a thought, as I ran into the same issue and thought I had a boost leak but couldn't find one. Ended up being the re/re for the AP.


Sent from my CIA monitored device
 


OP
eleven
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Location
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Thread Starter #3
Hey,

I would start by asking your tuner, as a diy, you could try and uninstall and reinstall your AP? Just a thought, as I ran into the same issue and thought I had a boost leak but couldn't find one. Ended up being the re/re for the AP.


Sent from my CIA monitored device
Thanks for the feedback. What is a "re/re"?
 


WeTheNorth

1000 Post Club
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#7
Ahhh gotcha! I unmarried and then remarried the AP and I have full boost at the moment.
Well hopefully you just had the same issue I was having, mine has been fine since I did the re/re. Iirc, you have the x37+FBO?


Sent from my CIA monitored device
 


OP
eleven
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Location
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Thread Starter #8
Well hopefully you just had the same issue I was having, mine has been fine since I did the re/re. Iirc, you have the x37+FBO?


Sent from my CIA monitored device
No, I have yet to upgrade the turbo.
 


OP
eleven
Messages
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Location
Kansas City
Thread Starter #9
Bumping this again as it's happening again. This time on my 93 tune. I'm not sure if it's the AP3 or a mechanical issue. No other issues or clues as to why this happening. Surely I'm not the only one.
 


Hijinx

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U.S. Air Force Veteran
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#10
Get logs of it while it's happening and send it to your tuner. It doesn't matter who the tuner is, if you're experiencing an issue nothing can be done if no one can see it while it's happening.
 


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