Tuning an 04 sierra denali with a swapped ls3 and whipple with 90mm throttle body. PCM will only command up to 32 g/sec at idle but desired will go much higher. Even with RTT if I command higher than 32 g/sec in the base running airflow table the scanner will only show a max of 32 in the "idle base PN airflow" and "idle base gear airflow" PIDs. Whatever the difference is between the desired airflow and commanded airflow values the computer has to add with idle trims. So the blade will physically go open more it just will not preemptively add the air but choses to have to learn to add more. Something has to be limiting it even though the base running table is set higher than 32. This creates a problem at cold engine temps, when I put in gear the engine bogs and has to add with trims. Why will the pcm not command more than 32 g/sec? This PCM acts goofy. I also noticed when I adjust the throttle scalar for the 90mm TB the PCM will not add follower or cracker. The scanner shows they are being added but in fact the throttle body blade/ tps indicate none is actually being added. The rpms drop till the STIT catches up. What gives? I attached the tune but not sure if it will tell you anything.
Don't mind the WOT stuff, the maf is maxed and he's only running a 1 bar for now.
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