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Discussion Starter · #1 ·
My TB sometimes makes a loud almost blower sound that usually only lasts for a minute or so. Most times it goes away when I hit the gas hard. Yesterday it lasted for almost 10 minutes. Anybody else getting this ?. I have heard it on some Chevy's passing by before.
 

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Could it be the engine fan clutch? When you push the gas does the noise get louder? I know that the fan clutch sometimes starts to act up and makes a loud blower noise like if you had a big fan and spun it really fast (mainly because thats what it is)
 

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I listened to the attached video and it's not the same sound. Mine sounds more "windy" than mechanical

Could it be the engine fan clutch? When you push the gas does the noise get louder? I know that the fan clutch sometimes starts to act up and makes a loud blower noise like if you had a big fan and spun it really fast (mainly because thats what it is)
Yes it does sound like a big fan and gets louder when I hit the gas
 

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Next time it does it try running the car with the hood open and listen for it, its probably the fan clutch going out or maybe your temp sensor is reading too high and causing your fan to kick in high, do you notice your temp going high? if you have a multimeter flip it to check the resistance, turn the car on for a while and let it get warm then check the resistance on the temp sensor, (there is a plugin you can unplug and hook your meter up to to check it) then wait a while for it to cool down and check it again. the resistance should have changed. If it hasnt then the sensor is probably going bad.

I attached a link about checking resistance with a meter.

http://www.ladyada.net/library/metertut/resistance.html

if the can clutch is going out its about $150 to get a new one, i wouldnt trust one from a junk yard.
 

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Discussion Starter · #6 ·
Next time it does it try running the car with the hood open and listen for it, its probably the fan clutch going out or maybe your temp sensor is reading too high and causing your fan to kick in high, do you notice your temp going high? if you have a multimeter flip it to check the resistance, turn the car on for a while and let it get warm then check the resistance on the temp sensor, (there is a plugin you can unplug and hook your meter up to to check it) then wait a while for it to cool down and check it again. the resistance should have changed. If it hasnt then the sensor is probably going bad.

I attached a link about checking resistance with a meter.

http://www.ladyada.net/library/metertut/resistance.html

if the can clutch is going out its about $150 to get a new one, i wouldnt trust one from a junk yard.
Thanks for the advise, I'll check it out.
 

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Fan clutches before 2005 were misdesigned and have a horrible failure rate. Sometimes they just die and lock on, causing a noise like an F16 on afterburner when you get on the gas. Not always detectable at idle. Sometimes, as in this case, they deteriorate slowly, and the initial 1 minute warm-up extends to 5, 10, or 15 minutes.

Lots of reading you can do in a search for "fan clutch"

If the temp gauge is at its normal position of within a needle width of 210, then it's probably not the temp sensor.

Note there is also a software flash update available around 2005 that takes advantage of the new fan clutch performance, and adds a function to run it faster on initial engine start-up, even if the coolant temp wouldn't demand fan cooling - to aid AC performance. Especially if you're in a place with 90-100 temps, you might benefit from paying the dealer to install this update.
 

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Discussion Starter · #8 ·
Fan clutches before 2005 were misdesigned and have a horrible failure rate. Sometimes they just die and lock on, causing a noise like an F16 on afterburner when you get on the gas. Not always detectable at idle. Sometimes, as in this case, they deteriorate slowly, and the initial 1 minute warm-up extends to 5, 10, or 15 minutes.

Lots of reading you can do in a search for "fan clutch"

If the temp gauge is at its normal position of within a needle width of 210, then it's probably not the temp sensor.

Note there is also a software flash update available around 2005 that takes advantage of the new fan clutch performance, and adds a function to run it faster on initial engine start-up, even if the coolant temp wouldn't demand fan cooling - to aid AC performance. Especially if you're in a place with 90-100 temps, you might benefit from paying the dealer to install this update.
From your text, (and if that is the problem I'm experiencing) it doesn't sound as if this is a fatal issue that will stop me in the middle of a long haul, correct ?. If the fan clutch is failing and doesn't release and my coolant temperature is within range, I just have to deal with the noise and not be concerned with an imminent breakdown ?
 

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You're right. Good analysis. Worst thing a too-fast fan will do is waste power and cost you a bit of mileage. Main reason they use the electroviscous fan clutch for in the first place. They never seem to fail the other way - not spinning - but that would only be a problem in stop and go traffic or extreme temps. Even a missing fan won't stop you from driving along as long as you don't stop for too long and you watch the temp like a hawk.
 

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Discussion Starter · #10 ·
You're right. Good analysis. Worst thing a too-fast fan will do is waste power and cost you a bit of mileage. Main reason they use the electroviscous fan clutch for in the first place. They never seem to fail the other way - not spinning - but that would only be a problem in stop and go traffic or extreme temps. Even a missing fan won't stop you from driving along as long as you don't stop for too long and you watch the temp like a hawk.
thank you
 
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