Ok I had antifreeze coming out of my overflow tank yesterday and it happened the day before also..the thing is it only does it when i park it and not everytime..could this be a thermostat issue? I had it replaced back in June so im starting simple...also in June before i replaced the thermostat, they did a pressure check and all was good but can that change from then to now? Since then Ive put over 1000 miles on my car and wondering if I have a blown head gasket...any info would help as I am limited to money on what to spend...

 

May want to put in a new radiator cap before going for the gusto.

 

will that help with the overheating? i bought a thermostat and gasket still will replacing that help?

 

I was going to suggest the cap as well. The radiator cap has a pressure rating, and will release coolant into the overflow if and when the cooling system reaches that point. If the cap is malfunctioning, and letting loose too soon, it would be doing what you are experiencing (burping after the car sits), due to the fact that heat and pressure still builds somewhat after you shut down the engine.

 

It was a bad radiator cap and the mechanic warrantied it and replaced it for free but the thing is it was on the car for less then a year is it normal for these caps to go out so soon??

 

No, it's not normal but there are a lot of crappy Chinese-made parts floating around out there. Even well-established high-end manufacturers like Bosch are sourcing parts from China. Quality is spotty.

You don't say what year car you have but I learned something the hard way on my 94/3400: the engine cooling fan does not turn on until coolant temp reaches something like 230F. Yes, you read that right. So if you don't have a good radiator cap the coolant will boil out before the fan comes on even if all else is well. As you've discovered...