06 pilot heat first gone in the front (all vents). Hot heat in the rear. Replaced heater control valve, flushed heater core, replaced thermostat, all vents now blow lukewarm air. Dealership says it is the heater core. Temp on hoses read 190 degrees yet the temp is reading 105 going thru the firewall. Is this possible or do we need to keep checking for something else?