1986 Toyota Cressida Heater works sometimes

WHEN YOU ARE IN THE "NO HEAT" MODE AND THE VEHICLE IS AT OPERATING TEMPERATURE, FEEL THE 2 HEATER HOSES THAT GO INTO THE FIREWALL (TO THE HEATER CORE)

IF BOTH OF THOSE PUPPIES ARE HOT TO TOUCH, THEN YOU ARE GETTING CIRCULATION THRU THE CORE, THE PROBLEM WOULD PROBABLY BE IN THE HVAC UNIT ITSELF. SUCH AS STUCK BLEND DOORS/ ACTUATOR BROKEN OR IT'S LINKAGE LOOSE.

EVEN LOOSE/ CRACKED/ BROKE VACUUM LINES (TO A VACUUM ACTUATOR)

CHECK CONNECTIONS

LET'S RETURN TO THE BEGINNING

THIS TIME YOUR TOP RADIATOR HOSE IS GOOD AND HOT, BUT THE HEATER HOSES ARE NOT REAL HOT. THE HEATER CORE MAY BE STOPPED UP.

IF THIS IS THE CASE, LET ME KNOW, I RECENTLY UNSTOPPED ONE AND TOOK A FEW PICS. MAYBE THEY CAME OUT DECENT AND I CAN LABEL WHAT I WAS DOING.

KEEP US POSTED ON WHATEVER YOU FIND

THE MEDIC