2003 Protege 5 overheating on long runs (> 20 min). Overheated today while driving at interstate speeds for > 15 min. Lost the coolant. Refilled with coolant. Return drive maintained normal engine temp if heater set to full heat. When set to cool interior air, engine temps slowly increase. Recovers when interior temp set to hot. Right fan (from front bumper looking into the engine) functions. Left fan does not operate. Bob
Cars & Trucks - Mazda - Protege - 2003 Mazda Protege
Answers & Comments
I just replaced the radiator and thermostat on my 03. The radiator was defective (corroded) on the lip where the cap seals. This allowed coolant to be spat out. The thermostat was also sticking closed after new radiator and this caused overheating. Replace both while in there for under $100 if doing it yourself.
Sounds like you have coolant leak if you are loosing coolant or a bad thermostat. I would replace the thermostat, they run about $10. The other fan is an aux fan and will only run when the a/c unit is on.