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Q: Why is my car leaking antifreeze?

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I am filling my antifreeze at least every other day. My heater barely works, and only in the defrost setting. The other night it was about 35 degrees and I drove less than 5 miles and the temperature gauge lit up and the temp was almost maxed out. Every now and then I hear a boiling sound coming from the engine. When I got my car in 2003, I had a coolant leak. A month ago the head gasket was replaced. Before the head gasket got replaced, I smelled burning antifreeze, but that was gone after that problem was dealt with until the temp light went on, then I could smell antifreeze again. Any suggestions?

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

Based on your description it sounds like your engine is overheating and the overheating is accompanied by a coolant leak. Coolant leaks can be both a cause and a consequence of overheating. Consequently, once the leak is repaired, your vehicle will be tested to determine if an overheating condition still exists. In all events, you may have to replace your engine cooling thermostat because episodes of overheating can damage the thermostat. If the thermostat is damaged, and left in place, that can set the stage for future cooling system problems.


Be sure not to drive the car if it is overheating because overheating can warp the cylinder head and/or engine block causing costly damage. The most common causes of overheating include low coolant level (including that due to the leak you are experiencing), a faulty thermostat, a plugged radiator, a faulty radiator pressure cap, collapsed hoses, non functioning cooling fans, and a faulty water pump or drive belt. Certain engine faults, such as a leaking head gasket or poor engine running condition can also cause overheating. If you desire that this problem be diagnosed by a certified Mechanic, dispatched by YourMechanic right to your location, please request an engine cooling system leak diagnostic and the responding certified mechanic will deal with the leak identification and repair first and then determine if the car is still overheating. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

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