Im tuning a friends car to idle and drive good. It idles fine, and it also drives great already, It does not stall on deceleration or hard braking. But on startup it just starts and dies right away. It is really weird because before it was starting right away. I even tried the previous tune and no change, still starts and dies. I went back to my current tune and added airflow, tried adding spark, tried more fuel but nothing makes a difference.
I was thinking maybe the throttle body is bad?? Another friend had similar issues with his ls3 throttle body and switched for a truck throttle and stopped having issues on start up.
Anyone have had this problem before? I feel like i tried everything and it acts the same. Might it be the throttle body?