Q: Where is my coolant going? My car keeps overheating and blowing cold air. The temperature rises when stopped and drops when accelerating.

asked by on March 12, 2017

my car keeps over heating. the coolant reservoir and radiator have been bled and filled twice within the last two days and when I checked the reservoir this morning it was down to almost nothing. the temperature will rise when I am stopped, at a red light lets say. and blow freezing cold air and as soon as I accelerate to about 50kph, the warm air will start blowing through and the temperature gauge will go back to normal (about a 25% of the gauge, red being 100%). it has been brought to 2 mechanics so far and neither of them can figure out the problem. could it be a faulty hose? or worst case scenario, my head gasket?

My car has 223 miles.
My car has an automatic transmission.

Look everywhere around the engine and see if there is a split hose or loose hose clamp. If the hoses and clamps are in good shape and tight, then check the core plugs (freeze plugs) and see if there is any residue that indicates a leak. If there is no residue or core plug leak, then take the dipstick out of the engine and see if the oil is milky or not. If the oil is milky, then a head gasket is burned and water is getting pushed into the oil system. If the oil is normal color, then the cooling fans may not be working properly and causing the coolant to boil out of the overflow tubes. This would explain why the vehicle overheats when sitting but runs cool when in motion. Check the fans to see if they are working. If the fans are not coming on, then the fan motor relay, fuse, or motor could be all burned out making the fans not work. If you need further assistance with your engine overheating at a stationary position, then seek out a professional, such as one from Your Mechanic, to help you.

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