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Discussion Starter #1
i have noticed this on the freeway when i let off after accelerating hard, and i really noticed it on my dyno runs, when i let off my truck still hazes black smoke out of the exhaust, has anyone seen this or is it something to be worried about? the truck has 230k miles on it with all the mods in my sig.
thank you
 

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I'm That Guy...
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Check for boost leaks..
 

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Do you let off quick? Cause if so, it takes a second for the ECM to adjust and will still be throwing fuel until all the parameters are met and the ECM stops sending fuel.
 

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Discussion Starter #4
Ill check for boost leaks, and what raven says makes sense because on the dyno i have floored and then let right off, and when im on the freeway ill let off slower and see if it does it, it only seems to do it at higher rpms.
 

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i have noticed this on the freeway when i let off after accelerating hard, and i really noticed it on my dyno runs, when i let off my truck still hazes black smoke out of the exhaust, has anyone seen this or is it something to be worried about? the truck has 230k miles on it with all the mods in my sig.
thank you
Reading your sig, I assume your FPRV is shimmed and not using a race plug?


You might be experiencing crankcase blowby burn off too


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