It seems that I've finally fixed it. The problem started right after I put a stainless steel nozzle in the printer so I bought some brass nozzles and it's been fine. The only thing I can figure is that the stainless nozzles had more threads and they stuck out of the heater block a bit more. I'm thinking maybe that extra few threads was just too far for heat to transfer reliably? I don't know if that makes sense but it's the only thing I've come up with. I realize different materials conduct heat differently but I've never noticed where anyone said they needed vastly different temps when chainging from brass to stainless steel nozzles. With brass I can run 195 with 100% fan, with my stainless nozzle that was too long I could barely run the fan even as hot as 230. When the current brass nozzle wears I'll try again but I'm going to cut the stainless steel nozzles down to the correct length first.