Getting back in to the summer tuning mode and was playing around with OL idle and whatnot.
Anyway, I was looking at my datalog from this morning and noticed that my LTFT was at +5-7% at cruising speed early on in my drive and AFR's were reporting richer than commanded.
Once it went into closed loop, LAMBSE started leaning out to hit stoich.
After about 5 minutes of driving, ECT was at operating temp and LFTT starting coming down.
It only took about 2 minutes of highway driving before LTFT were back to about 2%.
I thought it was odd.
I went back to last nights datalog and noticed, for some reason, when the AC compressor kicked on and IAC jumped up to compensate, my LTFT jumped from -2% to +7%, instantly like a switch.
I also noticed when that happened, AFR dropped down by 0.5-0.75 AFR (LAMBSE stayed constant due to OL idle). This makes sense as it's adding 7% more fuel. When the compressor disengages and IAC dropped down, LTFT dropped down as well.
I will say, I haven't cleared KAM in at least a week, but still seems odd.
Not the best image, but if you focus on columns F, G, H at the yellow line, you can see the jump.
Then, look at column S (AFR) which drops down when the LTFT jumps up.
This is idling at a stop light.
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Any thoughts on this?