04 silvy lq4, need overview.

hello all i have been tuning my 04 silverado CC 2500( CAI,NNBS 87mm intake swap, LTs, no cats,efans,ls2 coils) i have the hp tuners pro, at first i did a NB sd ve and maf tune, than i got an lc1 and did sd ve and maf tune, i tried a couple WOT pulls and noticed on decel with not hitting the throttle it spikes right after regains itself than spikes 21 and hangs there and the NB reads 0, here is my last tune, 2 logs and my config, im looking for guidance as i am new but have been doing lots of reading and such, thank you for you time.Attachment 42033Attachment 42034Attachment 42035Attachment 42036

Probably DFCO (Deceleration Fuel Cut Off). The VE table and MAF curve should be smooth. Also get all the negative numbers out of your main spark table

hi again, its winter time here and the temps are -10 to -40c pretty much all the time, i noticed when scanning my commanded afr goes from 14.68 to 16.00 and sometimes it richens up to 13.51, i noticed IAT temps on steady state on hiway is around -10 to - 22f i was wondering if the lower IAT temps will change the fueling, attached is the tune and a scan log where it hits both lean and rich commanded, i dont have a WB hooked up now as i already did tuning with it and reenabled all open loop stft and ltfts to rescan, i wads just wondering why it would command different afrs at steady state driving, thanks for any info.

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Originally Posted by xtremesilvy

hi again, its winter time here and the temps are -10 to -40c pretty much all the time, i noticed when scanning my commanded afr goes from 14.68 to 16.00 and sometimes it richens up to 13.51, i noticed IAT temps on steady state on hiway is around -10 to - 22f i was wondering if the lower IAT temps will change the fueling, attached is the tune and a scan log where it hits both lean and rich commanded, i dont have a WB hooked up now as i already did tuning with it and reenabled all open loop stft and ltfts to rescan, i wads just wondering why it would command different afrs at steady state driving, thanks for any info.

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That's normal, IIRC its an emissions test and not much you can do about it but ignore it. You'll notice once your commanded goes back to 14.6 or whatever you have it set at the stft will re-enable and go back to normal operating.