You may have got air trapped in the coolant system when refilling try bleeding the sytem. Or drain and refill coolant system with engine running to prevent air pockets.
BASIC HEATER SYSTEM TROUBLE SHOOTING CHART
CONDITIONPOSSIBLE CAUSE
Insufficient, Erratic, or No HeatLow Coolant Level
. Incorrect thermostat.
. Restricted coolant flow through core.
. Heater hoses plugged.
. Misadjusted control cable.
. Sticking heater control valve.
. Vacuum hose leaking.
. Vacuum hose blocked.
. Vacuum motors inoperative.
. Blocked air inlet.
. Inoperative heater blower motor.
. Oil residue on heater core fins.
. Dirt on heater core fins
Friday, March 1st, 2019 AT 6:24 PM
(Merged)