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hot air/whistle sound/low idle

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Old 12-23-2010, 09:57 PM
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Exclamation hot air/whistle sound/low idle

so i have a minor issues with my n/a.

1. when im driving on the freeway and such. hot air gets blown through the vents even when the heater or a/c are off. this only happens when i drive at faster speeds. my theory is that the air blowing into the air is somehow pushing the hot air inside the car. no idea what would cause that. i see it happen to alot of cars not just mine. many makes and models.

2. also when i rev the engine(like when staying in a gear for to long before shifting) i hear a small air whistle sound. like the type of sound you would hear when the air is blowing really hard. once i do shift, i can hear the sound slowly quieting down. vacuum leak maybe?

3. sometimes when i first start up the car it well idle at like 5-6rpm. and when i give it gas, it revs up very slow. once i rev it up a bit it goes away and idles around 7-9rpm. i think something to do with the choke or something.

thanks in advance
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Old 12-24-2010, 10:00 AM
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1. Vacuum leak. Replace the vacuum lines.

2. Intake leak. Check all intake connections.

3. Probably related to above.
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Old 12-28-2010, 10:26 AM
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so i looked under the hood this morning and OMG WTF. the ac lines are frozen solid! not sure how this happen or if it contributes to any of the issues above. i still havent found where the whistling found is coming from... heres some pics....
Attached Thumbnails hot air/whistle sound/low idle-imag0022.jpg   hot air/whistle sound/low idle-imag0023.jpg  
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Old 12-28-2010, 05:25 PM
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AC lines frozen mean you are low on freon. take AZ Bum advice and look for vacuum leaks. do a search many ways to do this explained in great detail elsewhere.
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Old 01-15-2011, 11:03 PM
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Update. so issue #2 was actually the new intake filter i put in so thats cool. i didnt find any vacuum leaks. when i do turn on my lights tho the rpms do take a big dump of like 200rpm frm like 900 to 700rpm. im also going to remove the ac system... im never going to be able to use it here anyways.... its too damn cold.
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