Hi:
This sounds interesting. Check both the coolant and oil to make sure nothing is getting into them (coolant into oil / oil into coolant) Next, when the vehicle is hot and you turn the engine off and it boils, check all hoses to make sure none of them have collapsed causing no circulation.
Keep in mind, all auto cooling systems are pressurized and you should never remove the cap when the vehicle is hot.
Let me know what you find.
Joe
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Wednesday, October 22nd, 2008 AT 10:06 AM