I'm having this same issue. Built up a 7 wrap 26g SS316L pair of coils. Put them on a sapor, wicked them up and the juiced them. The first pull was pretty good. Ohms were locked in at 0.21. Then it hit temp protect instantly and the voltage was wildly erratic. Exactly like this. I've been asking around to see if anyone has figured out why this happens but I can't seem to find anything. I'll keep looking though.