Reader Question: I have a 1990 Toyota 2WD drive Pickup Truck. The heater does not get very warm and the gauge barely rises above the minimum line.
Do I need to change the thermostat and /or heater core?
If the two radiator hoses are not very hot to the touch after the engine has had ample time to get to normal operating temperature I would probably start with replacing the thermostat.
Of course, check the coolant level inside the radiator first…not just look inside the plastic overflow bottle, but inside the radiator. Low coolant levels will cause this problem too.
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