Q: Car keeps overheating and losing antifreeze. Thermostat and hoses are all fine. What else could it be?

asked by on October 19, 2016

the car keeps overheating and losing antifreeze. i checked the hoses and the thermostat. Engine oil looks normal. there is also a rattling sound when driven. everything i checked is fine but still overheats. what else could it be?

My car has 130000 miles.
My car has an automatic transmission.

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Hi. I believe your Hyundai has a blown head gasket. This failure mode may not contaminate engine oil with coolant as sometimes occurs. The lost coolant may go into the cylinder or the exhaust instead. A slightly sweet smell from the exhaust pipe, with or without white smoke/steam would confirm this diagnosis. A certified technician from YourMechanic can come to your car’s location to inspect the overheating problem and pinpoint any faults that need repair.

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