Cadillac CTS-V 2004-2007 (Gen I) The Caddy with an Attitude...

nasty whine under hood. dead accessory?

Old 06-20-2013, 12:37 AM
  #1  
TECH Enthusiast
Thread Starter
iTrader: (3)
 
Cadzilla's Avatar
 
Join Date: Apr 2008
Posts: 507
Likes: 0
Received 1 Like on 1 Post
Default nasty whine under hood. dead accessory?

Hey guys, I have a nasty whine coming from under the hood... Hoping someone can help me pinpoint the cause.

here are some facts-

-04v, 79k mi
-sound is rpm related, not speed
-moans and groans bad at idle, whine/pitch increases up to about 1500-2k, then goes away (or gets drowned by the engine noise)
-clutch in/out doesn't affect pitch
-whine only occurs with the serpentine belt on, remove it and the sound disappears
-sounds like it's occurring directly below steering pump but can't tell where
-turning wheel does not change the pitch at all, steering seems completely unrelated
-in neutral I can almost feel a buzz in the shifter as it groans, same feeling when driving
-zero coolant smell..
-water pump was replaced about 40k mi ago
-battery voltage doesn't seem to be fluctuating or dropping, but I've only monitored for about 12 miles today on way home from work
-no pulleys seemed to generate any odd noises when spun

alternator dying? bad pulley/bearing? should I measure the volts on the battery while it's running?


I was going to drive to Michigan this weekend, but I guess I might be hosed now..


I uploaded a video at the link below, just remove the first h of the address. I would imbed it but don't want to break any rules: fyi, if you view it, click the small play button in the bottom left corner of the video, not the 'play' symbol in the middle, that's an ad. Recorded from the passenger side front wheel area before I popped the hood. Sound quality sucks. Enjoy the nice "V" rattle at shutdown.

hhttp://videobam.com/PXjHz

thanks
Old 06-20-2013, 04:25 AM
  #2  
TECH Senior Member
iTrader: (18)
 
itsslow98's Avatar
 
Join Date: Apr 2006
Location: Maryland
Posts: 6,768
Likes: 0
Received 4 Likes on 4 Posts

Default

Unplug the alternator while the car is running and see if it goes away. The one in my honda had the same symptoms and as soon as I pulled the plug it went away. Replaced it and all is well.
Old 06-20-2013, 01:22 PM
  #3  
TECH Enthusiast
 
Skidmarcx's Avatar
 
Join Date: May 2011
Location: Phoenix, AZ
Posts: 679
Likes: 0
Received 0 Likes on 0 Posts
Default

Sounds like the alternator since it is directly underneath the PS pump...
Old 06-20-2013, 01:30 PM
  #4  
TECH Addict
iTrader: (10)
 
NIKDSC5's Avatar
 
Join Date: Mar 2007
Location: DFW Area
Posts: 2,600
Received 22 Likes on 19 Posts

Default

Well, I'm hopeing that your V spontaneously grew a whipple!
Old 06-20-2013, 03:59 PM
  #5  
TECH Enthusiast
Thread Starter
iTrader: (3)
 
Cadzilla's Avatar
 
Join Date: Apr 2008
Posts: 507
Likes: 0
Received 1 Like on 1 Post
Default

ha, I wish! the sound went away today which is odd considering how bad it was yesterday.

my motor mounts are shot to hell too, so maybe the motor just shifted enough to put added stress on something.

I'll pull the alternator and get it tested, but probably replace regardless of results as preventative maintenance.

the voltage was ok both cruising and at idle
Old 06-21-2013, 08:42 AM
  #6  
11 Second Club
iTrader: (5)
 
Ballzee's Avatar
 
Join Date: Feb 2012
Location: North Florida
Posts: 536
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by NIKDSC5
Well, I'm hopeing that your V spontaneously grew a whipple!
when i read the title of this thread typing this^^^^ was my intentions.. so i will have to agree.. LOL
Old 06-21-2013, 09:27 AM
  #7  
TECH Enthusiast
 
UnsafeAtAnySpd's Avatar
 
Join Date: Aug 2007
Location: Wash., DC / Kabul, Afghanistan
Posts: 716
Likes: 0
Received 0 Likes on 0 Posts

Default

I've had both a bad PS pump and bad alternator. If I recall correctly, the PS pump would change tone by turning the wheel and the alternator sounded similar to what you're describing.

If you do replace it, check out the thread about an upgraded alternator.
Old 06-21-2013, 09:41 AM
  #8  
TECH Addict
iTrader: (5)
 
jerrad's Avatar
 
Join Date: Oct 2004
Location: NE Texas
Posts: 2,119
Likes: 0
Received 0 Likes on 0 Posts

Default

You can pull the belt and check your idlers.
Hope it's a cheap fix man.
Old 06-22-2013, 03:32 PM
  #9  
TECH Fanatic
iTrader: (12)
 
RADEoN's Avatar
 
Join Date: Mar 2010
Location: Harrison City, PA
Posts: 1,695
Received 6 Likes on 4 Posts

Default

definitely sounds like intermittent alternator whine. when it's screaming, pay attention to your volts on your DIC and see if they're out of range. If the alternator is struggling to produce amps, it'll try to make up for it in volts, which will then drop as well, if that makes sense.
Old 06-22-2013, 07:28 PM
  #10  
Launching!
iTrader: (2)
 
branland's Avatar
 
Join Date: Jan 2008
Posts: 233
Likes: 0
Received 0 Likes on 0 Posts

Default

Mine made a similar sound; it turned out to be the serpentine belt. Well sort of. It was actually the crank pulley working its way out and making the belt ride on edge. Had to replace the pulley and pin it.
Old 06-23-2013, 03:05 PM
  #11  
TECH Apprentice
iTrader: (32)
 
98cobra's Avatar
 
Join Date: Dec 2008
Posts: 321
Likes: 0
Received 0 Likes on 0 Posts
Default

Maybe you have a supercharger and didn't notice.


Thread Tools
Search this Thread
Quick Reply: nasty whine under hood. dead accessory?



All times are GMT -5. The time now is 01:17 AM.