Hi all, trying to determine what feature is "catching" my idle on a throttle blip at first start up, either hot or cold, but stops doing that after a short run time and lets the car die. Cracker is zero'd in this tune file (doing that zero it and see the effect stuff) as i'm chasing all those typical big cam no VSS auto LS1 returning to idle issue so must be throttle follower but it stops working? Definitely a work in progress tune and i'm fairly noobish being a side-draft carb guy primarily. I can see the IAC counts not "holding" on the second blip in the scan file.
Car does this at all temperatures. Idle is high 13s AFR (wideband) and quite decent but the car struggles to revert to idle after throttle blips or off-throttle deceleration periods.
2000 LS1 swap, no VSS, SD tune, early FAST manifold, stock TB, 236/242 110 split.
45mins driving today. I'd call it a very subtle yet improved state of tune. Still exhibits all the same characteristics of stalling after blip and getting very doughy and dropping rpm after decel then starting to hunt. But it is better so thanks.
Here's a log after i tweaked my idle timing. I've noticed on this one that one narrowband 02 is dropping and it sometimes corresponds with the issues but is mostly at light throttle.after timing tweak.hpl
I then added a little throttle cracker where the airflow was zero'd previously which helped more.
Now there is a new issue as well. Periodically the engine will rev up, show around 2.7% throttle (which i think activates follower as the IAC count goes up) and just stay there. I get out, physically check throttle is shut, which it is, then turn car off/on again and all is fine.
Interestingly, this is the same amount it rose to when i opened the throttle screw further then reset the TPS. It's like it momentarily forgets its "new" zero point and reverts. Happened with my old and now new TPS. Voltage shows 0.67 and stays but position % increases and car holds revs. stuck throttle.hpl
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