I didn't ingnore you. I agree that colder air is denser, but I didn't have this problem when I first switched over to the SD tune. It was only after I had it retuned for meth that the colder weather caused it to lean out. Not to mention, it doesn't lean out the entire time. It starts off ok then spikes to high 11's low 12's and then comes back down to mid 11's after a second or two. Just seems kinda weird. I have no doubt that you know your s**t!