Relevant vehicle information:
2010 SS Camaro, 6spd, stock displacement LS3 with forged rods/pistons (unknown CR)
STS twin turbo kit, stock intake manifold/tb
221/223 .609/.610 116+4LSA (previous shop spec'd the cam)
Aeromotive pump, FAST rails, ID850 injectors, return system, regulated before rails @ 52psi
Car was "tuned" (and I use that term loosely) before we got it with a blown up motor
Tune is OL MAF-only
For the most part, I've been able to un-fubar the "tune" that was on the car (I saved over what was on there...pissed myself off as I now can't show anyone how terrible it was aside from the picture I took of the PE table). Car now runs fantastic except for 2 issues that I cannot for the life of me figure out.
1. Cold start is WAY lean, no matter what I've tried. I've cranked up the IVT gain to the point that it commands low 11s when cold, still pegs the wideband lean (unfortunately the AFX we use for tuning only reads to 16, so I can't tell you exactly how lean). Won't hold idle, stumbles its ass off when moving from a stop unless you get it over 2k rpm. Once the car is warmed up it starts fine, idles fine, etc. and goes to the commanded 11.3 @ WOT.
2. The first drive cycle of the day runs different than it does the rest of the day once the motor is warm, without touching the tune. I saved logs of this an hour ago - first log it's lean everywhere, turned the car off for a few minutes while I got food, got back in it and drove home with it rich everywhere. My knowledge of computers tells me this is completely irrational - the settings in the tune should tell the car to do the same thing every time, and with fuel trims turned off, it should run the same way every time.
Any ideas on these two issues is greatly appreciated, the car has been down since 2k13 in March and I'm sure the owner would like it back about as much as we'd like to get paid for all the work lol.
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