Please help with e3d V6 temp issue....ugg

hi - installed a new e3d V6/Titan mod on my Taz 6 and I can’t get the temp to remain at it’s setpoint - consistently about 10° below set point and fluctuating - done too many PID’s to count - sock on sock off, etc etc - even tried changing out the thermistor and heating element - same issue. I believe the thermistor is the same unit Lulz uses in the Taz 6 - it’s a 30W 24V heating element - kit is “made for” the Taz… help!