Q: Hot at idle and low when driving never stays in middle

asked by on October 12, 2016

Just replaced 3 freeze plugs and thermostat and radiator cap. Car won't hold stedy temp I have no leaks now and no heat maybe 2 min of heat then cool air.

My car has 167000 miles.
My car has an automatic transmission.

Hi. This sounds like the water pump is not circulating the antifreeze in the engine. When a water pump stops circulating the antifreeze as well as it should the car tends to run hot when it is at idle and cooler when you are moving because you increase the engine speed while moving causing the water pump to increase its speed. Another possibility is that the radiator is clogged and causing the flow of coolant to be restricted. I suggest you having a certified technician from YourMechanic come and diagnose your cars overheating condition to avoid any necessary repairs.

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