Quote from tylerraydrake1999 on May 16, 2021, 6:41 pm

Hey y’all, so I have my ultimate LS installed on a 6.0 LQ4/4l60e. The 6.0 has a balanced rotating assembly, cleaned and honed block, dome top pistons, ported 317 heads with PAC .660 springs, and a .640/.629 at 231/239 115 LSA camshaft. I built this engine myself to the best of my ability, and through how it has run so far, it’s proving to be good. Again. This far. The 4l60e has the trans go HD2 kit installed, and it has a 3k stall converter. All of this is in a 1989 IROC-Z. So on to my issues. I have gotten the car to run a few different times well. Never driven yet. When it runs well, and I go to start the engine back up, it just doesn’t want to run again. I’ve tried adjusting the computer to the best of my ability, and I’ve tried messing with the IAC screw. Again, a few times it’s ran well and I’ve been confident I had it sorted, but I go back to run it again and it’s issues all over. Currently, the car starts, and then idles down over a few seconds to a stumble and stall. Idle is set at 900 at the recommendation of Texas Speed based on the camshaft I have installed. Throttle doesn’t do anything for me really. IAC steps are around 80-90, I’ve adjusted them, and when the idle drops, they do as well, however they rested around 40 one time, and then the car stumbled and died. I’m lost as I’ve been trying to sort this out for a while. It lets me run it a few times and then I think it’s all sorted out, but it never fails to just stop running right on me. It is saving all of its settings properly. Does anyone have a direct list of things to go through to diagnose where my issue is and help me sort it? If so that would be great. Or just someone with extensive knowledge who can give me a hand in sorting this all out. Thanks in advance! I’ll try to post the latest video of what it does if it lets me.