My passport has been making loud ticking noises off and on for years now and for the past 6 months or so it has been very loud. All the sudden, the noise died down a great deal almost going completely unnoticeable. I was happy at first but then i noticed the fan in front of the radiator (you can see it thru the grill) wasnt working. What does this mean exactly? I'm assuming the fan is used to help keep the engine cool but is it ok if i dont replace it...i dont know how important it is and i'm low on money at the moment. Also, is that why my engine is much quieter now? Sorry, I'm a newbie when it comes to this stuff.