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Discussion Starter #1
Got my 2000 last week and have been driving it around whenever I could. I noticed a horrendous ticking fan noise that comes every once in a while, especially noticeable in city driving... It's audible even with the windows all closed and downright scary sounding from outside.

The sound does *not* vary with RPM (so perhaps it's not belt related?) and the fan seems to come on and off randomly - perhaps it's thermostat-controlled? For example, sometimes it comes on at a stoplight, and then if I rev the engine for a bit and the fan will slow down to a stop.

Any ideas??
 

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Discussion Starter #3
I just did the newspaper test on the clutch fan today. It doesn't stop it from spinning.. And the intermittant noise doesn't seem to be affected by the newspaper at all. What other intermittent (e.g., thermostat-controlled) fans are there? Is the radiator fan next in line?
 

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Does not sound like the fan clutch at all. It is 99% sure the electric fan in front of the radiator, near your kidney grills. The outer fan screen is pushed back into the blades slightly. When the fan turns on it nicks the area that is touching. When you rev the engine you circulate more coolant, which lowered the temp enough to turn the fan off, resulting in no more noise.

Try lightly pulling out on the area, and close your hood gently, so as to not push the grills into the fan. Then test drive. Also as a safety precaution, and to rule it out, make sure the clutched fan has all of it's blades and they dont looked cracked.
 

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Do forget the SAP (Secondary Air Pump), however, it should only turn on for the first 90 seconds when the car is started, usually when cold.

My SAP finally wnet from a sounding like a squealing dead animal to rattleling and soundling like a washing machine full of marbles that I can actually feel inside the cabin! I think the impeller is finally hitting the inside of the air pump.

Have a new one waiting to go on soon, just need weather to cooperate a bit.

As for the fan clutch, you should also be able to tell when the car is warmed up that the fan is only spinning about 20-30% of the water pump speed. I can visually see the fan is not turning as fast as the water pump on my car.
 
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