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Discussion Starter · #1 ·
Hello I have a 2009 Chevy Silverado with roughly 270,000 on the 4.8 motor.the truck is already In rough shape but the problem I am having with it is when I try to use the AC there are times it works or just makes a noise like it wants to turn on but fails.this happens when I try to use the hot or cold air and in most cases just doesn’t turn on. Along with this I have a rattling noise from what I believe is in the front passenger side from what I am able to hear. the noise only happens when I start the truck and also when 2 conditions are met 1.it is in drive 2.when I push the accelerator,the noise occurs when I am driving no matter the speed I hear a rattle

if anyone has any experience with any of these problems please drop any information
 

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With that many miles the rattle could be anything. To help eliminate items, I would disconnect the accessory drive belt and see if the noise goes away. Noise could be HVAC compressor. alternator water pump etc. or internal engine components. Do not run the engine more than a couple of minutes after belt removal.
 

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Silver, would he have a separate belt for the AC compressor?

The rattle in the dash may be a cracked dash, check the 4 corners of the air bag pocket
 

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Discussion Starter · #4 ·
With that many miles the rattle could be anything. To help eliminate items, I would disconnect the accessory drive belt and see if the noise goes away. Noise could be HVAC compressor. alternator water pump etc. or internal engine components. Do not run the engine more than a couple of minutes after belt removal.
Thanks for the information I will look into this and bring back any new info if anything changed thanks and merry Christmas
 

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Discussion Starter · #5 ·
Silver, would he have a separate belt for the AC compressor?

The rattle in the dash may be a cracked dash, check the 4 corners of the air bag pocket
The dash is cracked but the noise isn’t the rattle but I believe it is the motor that allows for ac, it makes a noise of it wanting to turn on but failing
 

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Silver, would he have a separate belt for the AC compressor?

The rattle in the dash may be a cracked dash, check the 4 corners of the air bag pocket
Very possibly a separate belt Ray. My 02 does have a separate belt for the compressor but I don't know about 2009.
 

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Geicofrog, if you are talking about the Blower motor for the HVAC then it is in the passenger side of the dash and could be faulty.
 

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Discussion Starter · #9 ·
With that many miles the rattle could be anything. To help eliminate items, I would disconnect the accessory drive belt and see if the noise goes away. Noise could be HVAC compressor. alternator water pump etc. or internal engine components. Do not run the engine more than a couple of minutes after belt removal.
Alright so I have taken off the main serpentine belt and my finding have been that the noise is gone so I know that it isn’t a engine problem but I couldn’t locate that noise to see what truly was the problem
 

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Discussion Starter · #10 ·
Alright so I have taken off the main serpentine belt and my finding have been that the noise is gone so I know that it isn’t a engine problem but I couldn’t locate that noise to see what truly was the problem
But after putting the belt back on the noise came back so believe it’s the belt for ac and crank or in that general area any clues?
 

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Take a long handled screw driver or some sort of tubing to your ear and touch spots where you think the noise could be. Generally it will be a pulley of some sort. You should hear it. Be aware of moving components so as not to get hurt. I use a mechanics stethoscope that I bought a long time ago from a auto store. It has an amplifier so help find small noises too.
 
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