Chrysler Repair: loss of antifreeze through overflow, muffler shop, radiator cap

Question
QUESTION: i have a 2002 Grand caravan 3.8. it keeps blowing antifreeze out of overflow hose/radiator cap.i have replaced thermostat and doesnt appear be any leaks or exhaust "odor" in radiator

ANSWER: Hi Joe,
If the pressurization occurs fairly early while the engine is still below 210F, then I would suspect a leak in one of the head gaskets. In addition to the possibility of exhaust odor in the radiator, you might also look when starting the engine from cold to see if there is an unusual amount of white smoke from the exhaust pipe which when allowed to condense on your hand carries an odor of anti-freese. That would be corroborative of such a leak. Also check to be sure the oil in not milky, another sign. If the only loss is from the pressure cap, then perhaps replacing the pressure cap is the next step you could try as it may not be sealing the system to its indicated pressure level shown on its label.
Roland

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QUESTION: thanks, I did replace cap,before sorry forgot to mention that. the problem did still exsist. there is no exhauswhite smoke,or anitfreeze odor.the oil is not Milky, I also had a code scan done w a Snap On asolus, nO CODES OR ENGINE LIGHT.

ANSWER: Hi Joe,
How does the temp gauge behave? When does the overflow begin, what does the temp show when this happens? When you say there is no odor of exhaust, was that based on the nose test only, or a measurement with an exhaust gas detector (try a radiator or muffler shop which will have such a tool). If the pressurization/overflow begins only when the engine gets fully warmed up, then it may be that your water pump is not working or the radiator is clogged up and needs to be reverse-flushed and if that doesn't work, replaced. Either exhaust gas leakage from the head gasket or a block/head crack, or the coolant is not being pumped effectively through the radiator to cool it down. Those are the approaches and questions you need to answer.
Roland

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QUESTION: it seems to happen as the car gets to noranl operating temp then discharges antifreeze. the temp will drop to below normal operting temp then. however it seems to discharge more fluid then next time you start it even after sitting for a while.

Answer
Hi Joe,
I would have the cooling system checked for exhaust gas presence because it really shouldn't overpressurize until the temp starts moving close to H on the gauge, and even then it shouldn't overflow until it hits H or stays close for a while. I think you have an exhaust gas leak getting into the cooling system, but only a test will tell you unless you sense antrifreeze odor in the exhaust gas/smoke from the tailpipe on a cold re-start. I assume you have a 50/50 mixture, if not then of course you won't smell antifreeze in the exhaust condenseate.
Roland