Generation III External Engine LS1 | LS6 | Bolt-Ons | Intakes | Exhaust | Ignition | Accessories
Sponsored by:
Sponsored by:

Strange noise at idle...feedback please

Thread Tools
 
Search this Thread
 
Old Jun 26, 2011 | 04:06 PM
  #1  
Raise's Avatar
Thread Starter
TECH Addict
20 Year Member
iTrader: (31)
 
Joined: Dec 2003
Posts: 2,152
Likes: 0
From: Virginia Beach, Va
Default Strange noise at idle...feedback please

I noticed this since I picked up my car a few months back when the car was bone stock, so I know it has nothing to do with mods Ive done. At idle standing away from the car I can hear a faint metallic sound. It is hard to describe, but it sounds like a bunch of paperclips rattling around in a can. I thought it may be a cat, but I just put on longtubes and an offroad y-pipe. Also, I cannot hear it from inside the car, nor when i put my head under the hood. I can only hear it from backing away from the car a few feet and it sounds like its coming from under the hood or underneath, definitely from the front endthough.Ive done a bit of searching but havent come up with anything other than broken catalyst and clutch issues. I should add my car only has 20k miles on it and just has lid, fra, headers and catback. Anyway, any ideas fellas?
Reply
Old Jun 27, 2011 | 09:53 PM
  #2  
Raise's Avatar
Thread Starter
TECH Addict
20 Year Member
iTrader: (31)
 
Joined: Dec 2003
Posts: 2,152
Likes: 0
From: Virginia Beach, Va
Default

nobody?
Reply
Old Jun 27, 2011 | 10:42 PM
  #3  
sjsingle1's Avatar
TECH Senior Member
15 Year Member
Photogenic
Photoriffic
Shutterbug
iTrader: (1)
 
Joined: Feb 2010
Posts: 6,755
Likes: 292
From: Fort Worth TX
Default

normal piston slap??
Reply
Old Jun 27, 2011 | 11:05 PM
  #4  
Big&Tasty TA's Avatar
Staging Lane
 
Joined: May 2011
Posts: 68
Likes: 0
Default

Well the Ls1 has reputations for having piston slap, but it should go away once the vehicle warms up. If it is still there once the vehicle is at operating temperature I would pop off the belt and start the car, Don’t run it for long, no more than 20 seconds, the point of this would be to eliminate any noises that can be coming from the things off the belt. If the noise is still there I would then look into the valve train. Pull off the covers and inspect the rockers and springs. If they are fine then I would continue searching the valvetrain, pushrods etc. There is a bulletin from GM on the ls1s having rocker arm failure. The needle bearings would go bad and the rockers would come apart. Hope this helped and good luck.

Bulletin Number #02-06-01-029
Reply
Old Jun 28, 2011 | 04:03 AM
  #5  
ls1 1990 VN's Avatar
TECH Fanatic
20 Year Member
 
Joined: Aug 2004
Posts: 1,373
Likes: 4
From: Auckland, Nth Is, New Zealand.
Default

Originally Posted by sjsingle1
normal piston slap??
He said he can't hear it from under the hood or inside the car....Piston slap you sure can.
Reply
Old Jun 28, 2011 | 09:15 AM
  #6  
HVYMTL's Avatar
TECH Apprentice
 
Joined: Feb 2011
Posts: 322
Likes: 0
From: Bentonville, AR
Default

Pilot bearing failure maybe? Mine made a lot of noise kinda like what you described before I pulled it with my clutch swap
Reply
Old Jun 30, 2011 | 10:24 PM
  #7  
Raise's Avatar
Thread Starter
TECH Addict
20 Year Member
iTrader: (31)
 
Joined: Dec 2003
Posts: 2,152
Likes: 0
From: Virginia Beach, Va
Default

Its certainly not piston slap, I know what that sounds like. And Ive owned enough LS1s to know if it was valvetrain related. Im thinkin Big&Tasty is onto something with accessories. I will pull the belt and see if it goes away, and go from there. Any other ideas?
Reply
Old Jul 1, 2011 | 02:09 PM
  #8  
szalkerous's Avatar
On The Tree
iTrader: (1)
 
Joined: Jun 2011
Posts: 191
Likes: 0
From: Amherst, NH
Default

Sounds like you have the same problem mine does.....

Does it go away if you turn your A/C on?

If so, A/C clutch bearing. I'm actually poking around right now looking for anyone else that's replaced one on here....

EDIT: Or there's an adjustment to the clutch.... a couple other threads on here detail it... I'm not sure which I'll need, but I'd think adjusting the clutch is a "free" fix if it works.... if not, a new clutch bearing...

EDIT AGAIN: A useful link I found in another thread: http://flashoffroad.com/Maintenance/...llyService.htm

Last edited by szalkerous; Jul 1, 2011 at 02:17 PM.
Reply
LS1 Tech Stories

The Best V8 Stories One Small Block at Time

story-0

6 Common C5 Corvette Failures and What's Involved In Repairing Them

 Pouria Savadkouei
story-1

Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

 Verdad Gallardo
story-2

Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

 Pouria Savadkouei
story-3

Top 10 Most Powerful Chevy Trucks Ever Made!

 
story-4

Hennessey's New Supercharged Silverado ZR2 Has 700 HP

 Verdad Gallardo
story-5

Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

 Verdad Gallardo
story-6

Awesome K5 Blazer Restomod Comes With C7 Corvette Power

 Verdad Gallardo
story-7

10 Camaros You Should Never Buy

 
story-8

10 LS Engine Myths That Refuse to Die

 Verdad Gallardo
story-9

Five Reasons the Camaro Was the Most Pivotal Player in the Pony Car Wars 2.0

 Brett Foote
Old Jul 1, 2011 | 05:10 PM
  #9  
Raise's Avatar
Thread Starter
TECH Addict
20 Year Member
iTrader: (31)
 
Joined: Dec 2003
Posts: 2,152
Likes: 0
From: Virginia Beach, Va
Default

I will have to check to see if it goes away when i turn my ac on
Reply
Old Jul 1, 2011 | 05:23 PM
  #10  
00pooterSS's Avatar
TECH Veteran
15 Year Member
Photogenic
Liked
Community Favorite
iTrader: (40)
 
Joined: Mar 2008
Posts: 4,920
Likes: 531
From: Dallas
Default

Mine is currently doing the SAME thing, can barely hear it under the hood if at all and not at all in the car, but 5 to 10 feet away it is very noticeable, I traced it down the other day to my A/C tensioner pulley.

Pull the belts off and crank it, if the noise stops spin the pulleys and listen for the loud one.

I found mine using a stethescope but I know most people dont have those. If you know what your doing you can use a long screwdriver or pry bar to listen through and figure out which pulley it is.

But it's much safer to just pull the belts and crank it up.
Reply




All times are GMT -5. The time now is 05:27 PM.

story-0
6 Common C5 Corvette Failures and What's Involved In Repairing Them

Slideshow: From wobbling harmonic balancers to failed EBCMs, these are the issues that define long-term C5 ownership and what repairs typically involve.

By Pouria Savadkouei | 2026-05-07 18:44:57


VIEW MORE
story-1
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.

By Verdad Gallardo | 2026-04-21 13:57:02


VIEW MORE
story-2
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...

By Pouria Savadkouei | 2026-04-16 10:05:15


VIEW MORE
story-3
Top 10 Most Powerful Chevy Trucks Ever Made!

Slideshow: Top ten most powerful Chevy trucks ever made

By | 2026-03-25 09:22:26


VIEW MORE
story-4
Hennessey's New Supercharged Silverado ZR2 Has 700 HP

Slideshow: Hennessey has turned the Silverado ZR2 into a 700-hp off-road monster with supercharged V8 power and a limited production run.

By Verdad Gallardo | 2026-03-24 18:57:52


VIEW MORE
story-5
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

Slideshow: A one-off sports car that looks like a vintage Italian exotic-but hides a C6 Corvette underneath-just sold for the price of a new mid-engine Corvette.

By Verdad Gallardo | 2026-03-23 18:53:41


VIEW MORE
story-6
Awesome K5 Blazer Restomod Comes With C7 Corvette Power

Slideshow: A heavily reworked 1972 K5 Blazer swaps its off-road roots for a low-slung street-focused build with modern V8 power.

By Verdad Gallardo | 2026-03-09 18:08:45


VIEW MORE
story-7
10 Camaros You Should Never Buy

Slideshow: There are thousands of used Camaros on the market but we think you should avoid these 10

By | 2026-02-17 17:09:30


VIEW MORE
story-8
10 LS Engine Myths That Refuse to Die

Slideshows: Which one of these myths do you believe?

By Verdad Gallardo | 2026-01-28 18:10:11


VIEW MORE
story-9
Five Reasons the Camaro Was the Most Pivotal Player in the Pony Car Wars 2.0

The world was a better place when it was still around.

By Brett Foote | 2026-01-23 09:20:37


VIEW MORE