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Idle tuning/stalling help
This is a 5.3/4L60E swapped into an older truck. Its got a summit truck cam (210/219), Stock 78?MM cable throttle body. 3000 stall converter. 0411 ECU.
I have the VE table tuned in over a wide area and it runs great in traffic, on highway etc. Also have the idle RAF tuned correctly (I think) using the Russ K methods found on this forum. The problem arises mostly I am stopped and changing from D to reverse etc and backing up with light throttle on/off etc. Rpm will drop to nearly 400 RPM at some spots.
Its a 2 Bar OS upgrade. Base tune was a 2002 5.3 truck, cable throttle. I have tweaked the throttle stop so IAC is 50-60 at hot idle. Problem really only is bad in reverse, I wonder if this is due to the added load from the line pressure increase in the trans in R.
I had played with the idle under/overspeed spark tables but they don't seem to be doing much. I have them so at 200 RPM under it should be adding 12 degrees, But in the log it seems like its only adding 1 or 2.
I took this short log of the issue.
Attachment 93308