Power on a Monday, feels stock on a Tuesday

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skyshadow07

On a mission to get below 4000lbs
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I've been having the weirdest issues with my SHO. I will have great power one day then be 1 second slower on another. I confirmed this with my dragy. I'm not getting any check engine lights. I changed the fuel pump. I'm not getting heavy knock. I'm about to pay for a different tune from another company to see if that's it.
 

SM105K

Streetlight Grand Prix Champ/ IG @fafomotorsports
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Tunes don't change. Usually something mechanical fails. Which fuel pump did you change? The in tank (LPFP) or the HPFP? Have you data logged it so see what your fuel pressures are during the run? How is the timing? You aren't getting heavy knock, but is something holding the timing back? Like wire chaffing, ect. How much boost are you making? I have seen cracked charge pipes and intercoolers start to leak when they get warm. Have also seen couplers do the samething.

So...fuel pressure (both), timing, and boost are the things I would look in a datalog first thing.
 

SeanDev

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Also you mentioned your not getting heavy knock, have you logged to see if any knock your getting is enough to retard timing?
 

skyshadow07

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Boost is 15+ under full throttle. I do see knock some times that does slightly retard timing (1-1.25) but I have those same reading on days that I'm making great power.
 

skyshadow07

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I need to get a better logger. I have the N-gauge and it logs much slower than all other loggers and only 25 parameters.
 

SeanDev

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I need to get a better logger. I have the N-gauge and it logs much slower than all other loggers and only 25 parameters.
Being a 2013, have you replaced the fuel module that was under recall? If not they will take of that for free.
 

jman1200

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But, I've had that module fail on me and it was a sporadic complete shutdown. Not a lack of power.
What is described could be (IMO), misfire, HPFP, turbo going out, stuck west gate, sensors...
 

Bluezone

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I've been having the weirdest issues with my SHO. I will have great power one day then be 1 second slower on another. I confirmed this with my dragy. I'm not getting any check engine lights. I changed the fuel pump. I'm not getting heavy knock. I'm about to pay for a different tune from another company to see if that's it.
Check for Boost leaks.
 

Steven Grappy

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I've been having the weirdest issues with my SHO. I will have great power one day then be 1 second slower on another. I confirmed this with my dragy. I'm not getting any check engine lights. I changed the fuel pump. I'm not getting heavy knock. I'm about to pay for a different tune from another company to see if that's it.
I guess I'm not the only one having the weird issue. I have a 2016 SHO and I experienced the same thing at times, Seems one day the car flies with all the power in the world, the next as you commented, it feels like stock. I have checked for codes and observed data with Snap-on scanner, Smoke tested for leaks. Please let me know what you find and I ill also do the same if I can find a resolve.
 

skyshadow07

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Definitely. If I get a good weather day and some time I will log some data for everyone to interpret.
 

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