Bad head gasket or cylinder head. Suggest to check air compressor before working on the head.
Pressure on a cooling system raises the boiling point of the liquid and aids in the efficiency of the system.
The radiator cap controls cooling system pressure.The radiator cap controls cooling system pressure.
There is a leak somewhere in the cooling system. Have the cooling system pressure tested for leaks.
The usual cause of cooling system pressure surges is a bad head gasket. The compression from the cylinders gets into the cooling system and raises the pressure. Have a mechanic run a compression test to see if there are any big pressure changes between the cylinders.
If you are losing coolant, you probably have a bad cylinder head gasket. Too much coolant system pressure will drop your engine oil pressure.
Pressure test ?? Cooling system? A/C? Fuel Pressure? Compression?
Hyundai got excellent cooling system, you might have a little hole in your radiator that affects cooling circulation pressure? check if you have tight cooling system pressure.COCORICO
19 bar
Keep the cooling system at a predetermined rate of pressure. Raise the boiling point. Allow excess pressure to escape. Allow the cooling system to withdraw coolant from the reservoir.
If this is for an S-Series, you don't have to, The system has a deairiation line and does it on its own.
To relieve excess pressure in cooling system exceeding predetermined value.
Your heater core has a leak, have the station pressure test your cooling system if it does not hold pressure you a leak in system