Engine Cooling problem
2001 Chrysler PT Cruiser 4 cyl Front Wheel Drive Automatic 105000 miles
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the radiator is full of water but the overflow runs almost empty after driving 20 miles and it starts bubbling/boiling the last of the fluid out the top of the overflow and radiator is full.

Are cooling fans comming on? If so then maybe a stuck thermostat run engine does coolant flow ie. by rad cap opening? Then shut off if top hose is hot and bottom hose cool then thermostat is stuck.