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Serpentine belt changes speed at idle.
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06-29-2015, 09:40 AM | #1 |
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Serpentine belt changes speed at idle.
Just noticed today after cold start a sound like the fan is running fast then slow. I usually just go after starting the car in the morning but today I was idling for a couple minutes in the driveway. I opened the hood and noticed the belt would speed up and slow down. I think I have heard this a few times before after cold start when I was stopped at a nearby signal. Is that normal? The rpm does not change...in fact nothing seems off..it's just a sound.
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06-29-2015, 10:33 AM | #2 | |
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The fan, btw, is electric and will vary in speed depending on what the DME tells it to run at.
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06-29-2015, 10:43 AM | #3 |
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The ac is off. I was kind,of thinking that the belt can only run faster if rpm change. Just from looking it is hard to tell. Maybe the dme is sending signal to the fan to speed up and slow down...probably not normal.
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06-29-2015, 10:57 AM | #4 | |
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Stop worrying.
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06-29-2015, 11:04 AM | #5 | |
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thanks. |
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06-29-2015, 11:11 AM | #6 |
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No prob. Enjoy the car. They are a ton of fun!!
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06-29-2015, 01:41 PM | #8 |
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Why, so they can charge him $175 diagnostic fee to say everything id fine? If he were still in warranty I would agree with you but I doubt he is.
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06-29-2015, 01:42 PM | #9 | |
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If he were still in warranty I would agree with you but I doubt he is.
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06-29-2015, 02:11 PM | #10 | |
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06-29-2015, 03:22 PM | #11 |
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If you're auxiliary fan is running faster than normal it's a good sign the waterpump is on it's way out.
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06-29-2015, 06:43 PM | #12 |
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