Which one of your vehicles is this on. Were all just shittin' in the wind trying to help you with a transfer case problem. I don't believe that there is such a thing as a 4x4 2.2l S-10 or blazer. Maybe you should ask in the 4x4 section of the forum they might be able to assist you a little better. And if your state is switching to OBD-2 scanning for inspection that doesn't seem like a drivablity problem or a reason for increased emissions. I don't see why it wouldn't pass. The check engine light is no better than any other light, you can reset the code but it'll surely come right back, the problem doesn't disappear when you reset it, just the light.