Hi, I need some serious help! I just got a Mazda protege5 (2002) and its overheating I have had the radiator replaced, along with the timing belt an thermostat but it continues to overheat. I can drive up hill, and on the highway for about two hours before it starts to overheat, I pull over and see the coolant not boiling but there is bubbles being pushed into the container...Myself, knowing nothing about cars pulled the radiator cap off (stupid mistake) and it spilled everywhere! I put water back into the radiator reservoir then it ran fine?! I'm at a lose with the car because I see no leaks, hear no fans, lose coolant quickly and the only thing that makes it better is adding water I looked for white smoke thinking it could be a head gasket but the three times it over heated I never saw smoke. PLEASE HELP ME!

 

Get the cooling system pressure tested.
Get a 'TK' test done ( tests for a blown head-gasket)
Check that the cooling fan/fans cut in when it gets hot.
Some cars you can remove the thermostat and run the cooling system without leaks to eliminate it.
Remove the top radiator hose & 1 of the heater hoses and fully flush the system forwards & backwards.

 

do a compression test. if you dont have any coolant leaks, a bad radiator cap or a bad thermostat, you might have a bad head gasket

 

Hi HollyJay. I hope you were able to fix your problem. I was going to post up about my problem, but My '02 Protege ES is doing the EXACT same thing. My boyfriend is at the parts store now getting a new thermostat & coolant and will come back home and flush the system and then hopefully my problem will be solved. Good luck!!