Yes, I agree the sensor in the head is giving me a higher temp reading than if I had it in the block or water pump. That being said I don't mind having a temp reading from the heads which is consistantly higher than block temp. It seems to me that it is much more reponsive to fuel inputs than the other locations. Now the clacking or loud ticking noises? Any input? Can I remove the valve covers & measure clearances @ the valves to see if one is receding?