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  #1  
Old 12-21-2006, 10:19 AM
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at trafflic lights, i can hear some motor kick in and my lights dim. what is this?

once a while when i'm stopped at a traffic light, i can feel/hear some motor kick in for a few seconds and then it stops. when the motor kicks in, my dash cluster lights dim for a split second too.

what is this motor and what does it do? it must be drawing lots of current to dim the cluster lights


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Old 12-21-2006, 11:03 AM
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Can you tell where the motor noise is coming from?
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Old 12-21-2006, 11:12 AM
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Answer:

Normal operation.

This is your electric auxiliary cooling fan turning on.





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Old 12-21-2006, 12:11 PM
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It's probably the secondary air injection pump. Some people say it sounds like a vacuum cleaner. Is it a really high-pitched whine?
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Old 12-21-2006, 01:28 PM
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Hmmm

Quote:
Originally Posted by ILUVMILS View Post
It's probably the secondary air injection pump. Some people say it sounds like a vacuum cleaner. Is it a really high-pitched whine?
Possible:
I only had one bad enough to dim the lights, and it shorted seven days later.
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Old 12-21-2006, 02:20 PM
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Quote:
Originally Posted by ILUVMILS View Post
It's probably the secondary air injection pump. Some people say it sounds like a vacuum cleaner. Is it a really high-pitched whine?


yes, sorta sounds like a high pitched whine. is that bad?
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Old 12-21-2006, 06:17 PM
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Quote:
Originally Posted by buckwheat View Post
On my motor's program (119), air pump is only on during initial start for 60 seconds. Blows more O2 into the cats to help them come up to temp. I have never found a trigger for this at other times - please help me verify. And you're right, it's quite similar to a vacuum cleaner/blower.
Air injection does indeed take place following cold-engine start, but the system self-test takes place after the coolant temperature is above 60C, and the vehicle comes to a stop.

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