Q&A

Where does the temperature gauge read? If it reads on the low side of the gauge after 10 or 15 minutes driving I would suspect a bad cooling system thermostat. Check with the engine running /warmed up the hoses going into the heater core, both should be hot if the heater controls are on full hot, if only one is hot check the heater controls are operating the heater valve and or try flushing out the heater core with the hoses disconnected see if the heater core is restricted with debris.
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