This is what happens, when I have the AC or the heat on, when I step on the gas (doesn't matter if it's on floor, panel, or AC) it swithces to defrost the whole time I step on the gas and once I let up it stops and goes back to what I had it set on at first. Is this normal or is somethin goin on that I should be aware of. Other than that there is nothing on that is a cause for concern, gauges are fine, runs like usual and no check engine lights. It's done this ever since my grandpa had it, he got it used with about 46,000 miles on it. I have put about 12,000 on it in my entire 5 years of having it. Very good condition.