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2015 Silverado 5.3 4x4 reg cab bogging down while slowly accelerating

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 The truck has around 128k miles 

recently it’s been having a issue that has gotten worse and worse overtime 

While driving let’s say a constant 30mph and if you press the gas just a little bit to get up to speed without stomping the accelerator the engine will create a bog down noise like if it’s retarding the timing by a lot and lately while doing this it now produces a cracking noise like sparks or knocking noise my friend hooked up his hp tuners and I had one code which did not light up the check engine light since it was pending the code was P0324 knocking sensors I went ahead and replaced both and the truck stayed the same while in this bog down state the hp tuners would notice the knock sensor going to red and the timing was set to -11 while in this bog down 

next I checked if any coils plugs or wires or any sensors MAF MAP cleaned I found two plugs loose and tighten them up and the truck stayed the same while inspecting the thorrtle body I noticed it was oily fresh oil on it (pcv gone bad?) I haven’t gotten to clean the throttle body or replace PCV and the sparkplugs were replaced about 20k miles ago 
so I’m just lost on what it could be fuel and spark looked good on hp tuner transmission as well no slip and rpms matching with engine 

Idles perfectly fine engine doesn’t overheat nor tranny and if I step on it 

it has great power and shifts fast it’s just when I want to gently press the pedal it doesn’t like it and retards the timing by -11 and makes godful sounds I tried octane booster but it did nothing as well only mods to the truck is a k&n which installed when I bought it 20k miles ago 

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See if your friend with hp tuners can disable the torque converter clutch in the special functions when it feels like it's bogging down. I'd be curious if the clutch isn't disengaging and bogging the engine down.

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will try that out next time i see him the truck is driving better now but it still bogs down imma try to clean the thorttle body but i have no clue why it would ****** the timing so much like if its choking might i add when i bought the truck it was 100% stock and i wouldnt ever hear it bog down but as soon as i put the k&n i started hearing it the bogging sound so idk if its related to that


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