300ZX (Z31) Forums Dedicated to 84-89 ZCars otherwize known as the Z31's

hot air/whistle sound/low idle

Thread Tools
 
Search this Thread
 
Old Dec 23, 2010 | 09:57 PM
  #1  
Flacster's Avatar
Thread Starter
Registered User
 
Joined: Sep 2010
Posts: 303
From: Portland, OR
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
Old Dec 24, 2010 | 10:00 AM
  #2  
AZ-ZBum's Avatar
Registered User
 
Joined: Jan 2005
Posts: 1,396
From: Phoenix, Arizona
1. Vacuum leak. Replace the vacuum lines.

2. Intake leak. Check all intake connections.

3. Probably related to above.
Old Dec 28, 2010 | 10:26 AM
  #3  
Flacster's Avatar
Thread Starter
Registered User
 
Joined: Sep 2010
Posts: 303
From: Portland, OR
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  
Old Dec 28, 2010 | 05:25 PM
  #4  
rogerz's Avatar
Grumpy & Helpful
 
Joined: Sep 2006
Posts: 1,415
From: Mill Creek WA
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.
Old Jan 15, 2011 | 11:03 PM
  #5  
Flacster's Avatar
Thread Starter
Registered User
 
Joined: Sep 2010
Posts: 303
From: Portland, OR
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.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
300zx1993
300ZX (Z32) Forums
1
Jun 8, 2013 07:21 PM
PredatorZ
300ZX (Z31) Performance / Technical
0
Oct 21, 2011 11:26 AM
ezAction83
300ZX (Z32) Performance / Technical
6
Sep 29, 2010 04:48 PM
kiboy6
280ZX (S130) Forums
28
Dec 13, 2008 01:53 AM
cm3
280ZX Performance / Technical
2
Sep 4, 2003 06:44 AM




All times are GMT -7. The time now is 12:39 PM.