i've been having problems with keeping the temperature down on my car lately, and what had happened is that all of my coolant(water/anti-freeze) had dissappeared. so i tossed in about a total jug of water/prestone mix and my car was happy again but just in case, i now keep a jug with a mix in the car at all times. anyway, i took my car to get the oil changed and stuff the other day before i went on vacation and the guy changing the oil said that i was leaking coolant... but he couldn't tell from where. the weird thing was that i've gone under my car on jackstands looking for any leaks and i've checked my drive-way (there are times my car is parked for a day or 2 straight) and stuff and i haven't seen any coolant leaking (just gas and a little bit of transmission fluid). the only thing i can assume is that when i had my radiator replaced with an aluminum one they didn't seal up all the connections correctly or something but i got it replaced about 3 or 4 months ago and the temperature control problem has only been happening to me lately. is there a possibility that one or multiple coolant passages on my engine may be leaking? if this were the case, would it be a good excuse to do the 2.4 swap?

my folks had a problem kinda like that with their Neon a while back. they replaced almost the entire cooling system and it turned out to be a small, hairline crack on the thermostat housing that would only vent steam and not create a leak. the less coolant in the system, the more steam would be vented until it would be bone dry. Just another idea...

could be leaking from the water pump to. also check the underneath of the lower radiator hose. it can rub up against the front motor mount bracket and have a small hole.

try running your car and throw it up on jack stands runnin and look for leaks , sometimes the leaks wont leak unless the car is running and the thermostat is open then the hoses have the pressure of driving to expose leaks. Its also a good idea when you flush your coolant system to remove both upper and lower hoses and replace the cheap stock clamps with the clamps that u can tighten with a screw driver(torque em good) . this is how i fixed my slow leak on my lower radiator hose. oh and if u take off your Hoses make sure you put them back on the way they came off.