Lately I have run across a difficult to diagnose problem with my 2001 Infiniti I 30. It seems that the cooling fan runs from the time the engine reaches operating temperature and it never cools the engine down such that the fan stops running. In addition, if I drive the car for about 1-2 hours nonstop on the highway it begins to overheat. The last time this happened I turned my heater on full and I was able to reduce the temperature enough to make it home without causing further damage(I hope!). I have replaced the thermostat twice, replaced the water pump and flushed the radiator, but the problem persists. I had a mechanic perform an engine diagnostic test, but he found nothing. I love the car, but I can’t drive it very far for fear of damaging the engine or getting stuck in the middle of nowhere. Can you offer any suggestions?
Has the coolant service been done regularly? Maybe your radiator is clogged and needs replacement.
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