New V2 purchase, immediately upgraded to E3D hot end. When doing PID autotune, the hot end will only reach 140 C, where it plateaus. Ultimately the autotune times out and fails. Any ideas what could be causing this? I'm sure it's something simple. Checking with an infrared temp gun shows that the thermistor is relatively accurate. Voltages are 11.5-11.6 at power supply, to hot end and to cooling fan. I have done PID autotunes at 125 and 135 degrees, and while values changed, they didn't increase top end temperature. I cannot achieve more than 140 C using manual controls either.. I appreciate the help and suggestions!