Radiator sprung a leak so we replaced it had amazing heat and no issues for about a week then the heat went to luke warm and the gauge would go up in the red stay there about 3 or 4 minuets and come down we changed the thermostat it still continued to do this. one day i would have good heat and no over heating then the next no heat and it would over heat a few times while driving then always go back down to normal after a few mins new water pump, coolant full, no drop in coolant at all so no leak there. both hoses to and from heater core are hot the radiator has been bled for air pockets by running it for 20 mins or so with the cap off but for the last week or so the gauge has been going completely to hot and not coming back down without shutting the car off to cool down and heat comes out cold. Had a mechanic run tests for cracked head gaskets and all that they are fine. Please help no one can figure out the problem
My car has an automatic transmission.
Hello - it sounds a bit like there are still air pockets in the cooling system. Make sure you are bleeding the cooling system with the heater valve turned to max heat, fan on High, and with the front of the vehicle "uphill" if possible, to help captured air find its way out, and a fast idle for 5-10 minutes. Also make sure the auxilliary radiator fan is coming when the temp goes up (or if the AC is turned on) as well. Your vehicle has a small radiator, and proper operation of the fan is critical to avoid overheating. For assistance, I recommend an overheating inspection performed by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, and give you an accurate assessment of damage and cost estimate for repairs.
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