Tech / General Engine Is your car making a strange sound or won't start? Thinking of adding power with a new combination? Need other technical information or engine specific advice? Don't see another board for your problem? Post it here!

Noise when shutting down sometimes

Thread Tools
 
Search this Thread
 
Old 03-12-2005, 10:05 PM
  #1  
Supreme Member

Thread Starter
 
Firebreed's Avatar
 
Join Date: Mar 2005
Location: Honolulu, HI
Posts: 1,539
Likes: 0
Received 0 Likes on 0 Posts
Car: 2011 SS/RS
Engine: LS3
Transmission: Tremic6060
Axle/Gears: good enough
Noise when shutting down sometimes

Well, every once in a while (doesnt happen everytime) when i shut down the engine, the engine contuies to rotate (although slowly) and as it rotates it makes a Knocking noise (no other time does it do this) Ive checked the Motor mounts, they were okay, i did rock the car from side to side, and on the driverside there was a knocking noize, im at a loss right now anybody else have this problem? anybody know what it is? Thanks in advance


Firebreed
Old 03-12-2005, 10:17 PM
  #2  
Moderator

 
IROCThe5.7L's Avatar
 
Join Date: Jul 2001
Location: Buffalo, NY
Posts: 5,196
Received 59 Likes on 40 Posts
Car: 1988 IROC-Z
Engine: 427 SBC
Transmission: ProBuilt 700R4
Axle/Gears: Moser 12 Bolt / 3.73 TrueTrac
Sounds like your motor is detonating when you turn your car off. Could be a timing issue. I had the same problem with my winter car and it was due to large vacuum leaks.
Old 03-12-2005, 10:28 PM
  #3  
Supreme Member

iTrader: (2)
 
dimented24x7's Avatar
 
Join Date: Jan 2002
Location: Moorestown, NJ
Posts: 9,962
Likes: 0
Received 3 Likes on 3 Posts
Car: 88 Camaro SC
Engine: SFI'd 350
Transmission: TKO 500
Axle/Gears: 9-bolt w/ 3.23's
The dieseling could be caused by lots of carbon deposits or too much timing.
Old 05-08-2005, 02:02 AM
  #4  
Supreme Member

Thread Starter
 
Firebreed's Avatar
 
Join Date: Mar 2005
Location: Honolulu, HI
Posts: 1,539
Likes: 0
Received 0 Likes on 0 Posts
Car: 2011 SS/RS
Engine: LS3
Transmission: Tremic6060
Axle/Gears: good enough
Well it isnt the timing.. So it must be the carbon depostits or something so obivious its being over looked I know i got one more vacume hose to replace so when i do that ill give another update here (wont be for a while because i just dont got enough money on me to afford 1.69 a foot for the size that i need... Ah the life of a poor white boy that cant find a job)



Firebreed
Old 05-08-2005, 02:52 AM
  #5  
Senior Member

 
SLEEPER 86's Avatar
 
Join Date: Jun 2003
Location: Carson City Nevada
Posts: 627
Likes: 0
Received 0 Likes on 0 Posts
Car: 86 coupe
Engine: 383
Transmission: 700r4
Axle/Gears: 9 bolt 3.27 posi
usually the carb is the problem in these instances,check the float level again,check fuel pressure,first i would make sure no fuel lines are running near a heat source.fuel percolation can cause pressure in the fuel line to rise to the point that the needle and seat are overridden.this can cause the run on you described.
what kind of carb do you have?
Eric
Old 05-08-2005, 03:02 AM
  #6  
Supreme Member
 
Angelis83LT's Avatar
 
Join Date: Mar 2005
Location: Spicer, MN
Posts: 1,121
Likes: 0
Received 0 Likes on 0 Posts
Car: '83 Berli, '84 Berli, '84 Z28 HO
Engine: L69, LG4, L69
Transmission: TH700-R4, TH700-R4, T-5
Axle/Gears: 3.08, 3.08, 3.73 Posi
I agre with the carb comment. Although in my experience it is due to the idle being set to high. if it is not at 750rpm in park on an auto, an instead running at like 900 or 1000 rpm. it will do the diesel thing. you need to adjust the idle speed down at that point until it is where it should be.

if you have deiseling becuase of timeing.. there is something pretty wrong. And the timing would have to be waaaayyyyy off. which would prolly result in other types of problems
Old 05-10-2005, 07:19 PM
  #7  
Supreme Member

Thread Starter
 
Firebreed's Avatar
 
Join Date: Mar 2005
Location: Honolulu, HI
Posts: 1,539
Likes: 0
Received 0 Likes on 0 Posts
Car: 2011 SS/RS
Engine: LS3
Transmission: Tremic6060
Axle/Gears: good enough
I got a rochester vera-jet 2-bbl carb, How would i check the float? (horable with carbs, first car that ever had a carb on it for me) ive played with the idle screw, and if i do one turn (one rachit click) clockwize the engine runs at about 1000rpm's (according to stock tach) one rachit click couterclockwize causes the engine to stall out.

Firebreed
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Gunner242
Electronics
7
12-25-2015 04:49 PM
sleprock
Interior Parts Wanted
2
10-03-2015 11:01 PM
sjorgens
Suspension and Chassis
7
10-01-2015 07:54 PM
ironbmt
Tech / General Engine
0
09-27-2015 06:00 AM



Quick Reply: Noise when shutting down sometimes



All times are GMT -5. The time now is 11:09 PM.