Ok...here's the situation. 08 E67 Trailblazer 5.3L (12618163). I brake and rev her up to about 1500 rpm at which point she starts to tug at and push through the brakes. I release the gas and she rolls out then kicks into high power around 2000 rpms. I know there is more power to be had at launch...but I can unleash it. So I logged it. Clearly the electronic throttle body is staying shut as seen in the log. BTM is set to YES. Now I've have tip in throttle and all torque management off or set high. B5208--> is zero'd except for 1000= 50. Traction control/Stabilitrak is OFF. But I can't for the life of me figure out what parameters I'm over looking that won't let that her launch with all she's got.
Any suggestions on where to focus my attention regarding the issue of the throttle's slow to open with brake torquing? I've attached the log...just jump up to frame 2260 and you'll see the note markers.
Log-->
SWEEET.efi