Well, gotta say... this LS2 Idle stuff is a whole lot different than LS1's. It's acting all kinds of crazy on me.
This is whats going on.
1. I'm currently tuning in SD and do not have plans right now to use a MAF. All other fuel adjustment aids turned off. Car is currently in OL
2. After every Calibration Write, Motor starts right up with a hesitation at 500 rpm, then up to commanded idle.
3. AFR starts at 16.7 (Idle) cold, then works itself down to 14.5 AFR (Hot)
4. During Warmup, the car is spitting a bunch of black stuff out of the tailpipes (maybe unburned gas) along with some strong fumes. (This problem sometimes goes away after a few days driving) Is idle learning something here??????
5. While driving around... all is great for about 10 mins, then when I get to a stop light the car will initially go to 950 idle, then jumps to 1200 idle and remains there for the duration of the drive. AFR is at 14.7 @ this point. Seems like something is overriding commanded idle????
6. Also at cold startup I occasionally get a slight surge during the first 10-15 secs. I can actually hear the motor changing it's whistling pitch here. (Maybe Startup AirFlow Table????)
I know this isn't much help without a log or tune attached, so please let me know what you guys want.
Startup Idle (Cold) - what parameters logged????
Startup Idle (Hot) - what parameters logged????
Tune
Any Idle Histograms out there for LS2's????
Thanks
Chris