Notices
Maintenance & Repair 350Z up keep and diagnosing/fixing problems

Rattling Sound when you turn off ignition

Thread Tools
 
Search this Thread
 
Old Dec 29, 2006 | 12:48 PM
  #1  
cruZin163's Avatar
cruZin163
Thread Starter
Registered User
 
Joined: Jul 2006
Posts: 36
Likes: 0
From: Pleasanton
Question Rattling Sound when you turn off ignition

Does anybody else noticed a Rattling Sound when you turn off ignition... The dealer said that is normal... Anybody have a second opinion?
Reply
Old Dec 29, 2006 | 12:57 PM
  #2  
Sean's Avatar
Sean
Registered User
 
Joined: Jan 2006
Posts: 8,719
Likes: 2
From: nj
Default

any chance it is engine knock? do you use low octane fuel (below 91) ?
Reply
Old Dec 29, 2006 | 02:39 PM
  #3  
MR_X's Avatar
MR_X
New Member
iTrader: (5)
 
Joined: Nov 2006
Posts: 3,503
Likes: 0
From: El Centro, Ca.
Default

I use California's finest 91 octane and I get it too. Noticed it this morning. But the engine shakes a little bit too.
Reply
Old Dec 29, 2006 | 02:41 PM
  #4  
06r33z's Avatar
06r33z
Registered User
iTrader: (2)
 
Joined: Jul 2006
Posts: 416
Likes: 0
From: socal
Default

they told me thats normal, i have that same noise
Reply
Old Dec 29, 2006 | 02:46 PM
  #5  
QuicksilverZ33's Avatar
QuicksilverZ33
Registered User
iTrader: (34)
 
Joined: Nov 2006
Posts: 920
Likes: 1
From: east coast
Default

I have the same noise...I think it is the transmission comeing to a stop because when I hold the clutch in and turn the car off...the noise is gone.....
Reply
Old Dec 29, 2006 | 02:48 PM
  #6  
97supratt's Avatar
97supratt
Registered User
iTrader: (61)
 
Joined: Nov 2004
Posts: 5,034
Likes: 3
From: Glendale California
Default

I have the same crappy noise. When the motor gets to a low enough rpm it shakes a bit more and you hear parts making noise. Usually its the engine and transmission.
Reply
Old Dec 29, 2006 | 04:13 PM
  #7  
Changvi's Avatar
Changvi
New Member
iTrader: (66)
 
Joined: Mar 2006
Posts: 3,453
Likes: 1
From: Somewhere
Default

Its normal. Don't sweat it.
Reply
Old Dec 29, 2006 | 05:15 PM
  #8  
DavesZ#3's Avatar
DavesZ#3
350Z-holic
Premier Member
20 Year Member
iTrader: (26)
 
Joined: Jul 2003
Posts: 15,887
Likes: 23
From: Louisiana
Default

Yeap, clutch out in neutral and turn off the engine and it sounds like a bunch of rocks rolling around under the car. It's "normal", even brand new Zs on the lot do it.
Reply
Old Dec 29, 2006 | 06:53 PM
  #9  
97supratt's Avatar
97supratt
Registered User
iTrader: (61)
 
Joined: Nov 2004
Posts: 5,034
Likes: 3
From: Glendale California
Default

Originally Posted by DavesZ#3
Yeap, clutch out in neutral and turn off the engine and it sounds like a bunch of rocks rolling around under the car. It's "normal", even brand new Zs on the lot do it.
I always press down on the clutch when turning off my z, it just doesn't sound right when its depressed. lol
Reply
Old Dec 29, 2006 | 07:01 PM
  #10  
eat rice z33's Avatar
eat rice z33
New Member
iTrader: (11)
 
Joined: Jun 2005
Posts: 1,553
Likes: 2
From: ct
Default

got the same noise. kinda funny i dont mind it hehe
Reply
Old Dec 29, 2006 | 08:44 PM
  #11  
ZSpectrum's Avatar
ZSpectrum
New Member
iTrader: (4)
 
Joined: Nov 2006
Posts: 3,718
Likes: 0
From: Dallas
Default

just push the clutch in and you wont hear it
Reply
Old Dec 29, 2006 | 11:39 PM
  #12  
350ztoronto's Avatar
350ztoronto
Registered User
iTrader: (10)
 
Joined: Sep 2005
Posts: 1,238
Likes: 0
From: toronto
Default

normal sounds like ur clutch is gonna fall off but its normal...
Reply
Old Dec 30, 2006 | 04:32 PM
  #13  
Kevins350z's Avatar
Kevins350z
Registered User
iTrader: (36)
 
Joined: Sep 2006
Posts: 633
Likes: 0
From: CA Bay Area
Default

Originally Posted by ZSpectrum
just push the clutch in and you wont hear it
+1
Reply
Old Dec 30, 2006 | 04:35 PM
  #14  
bleufiend's Avatar
bleufiend
Registered User
iTrader: (4)
 
Joined: Dec 2005
Posts: 593
Likes: 0
From: Lakeland FL
Default

<<<Nissan Tech.

Thank nissan for a subpar throwout bearing design. Thats what causes the stones rattling sound when shutting off the engine. Also is what causes the stone grinding sound when the clutch is released and the cars in neutral.
Reply
Old Dec 30, 2006 | 06:45 PM
  #15  
roast's Avatar
roast
Registered User
iTrader: (2)
 
Joined: Sep 2005
Posts: 4,092
Likes: 1
From: Okay, see?
Default

Originally Posted by bleufiend
<<<Nissan Tech.

Thank nissan for a subpar throwout bearing design. Thats what causes the stones rattling sound when shutting off the engine. Also is what causes the stone grinding sound when the clutch is released and the cars in neutral.


Question: Do you even know what a throwout bearing is?
Reply
Old Dec 30, 2006 | 07:39 PM
  #16  
bleufiend's Avatar
bleufiend
Registered User
iTrader: (4)
 
Joined: Dec 2005
Posts: 593
Likes: 0
From: Lakeland FL
Default

Yes and if you understood the operation of it you wouldnt of asked that question.

Its a combination of the throwout bearing/friction disc/pressure plate assembly developing just enough play between each other to cause the rattling. Mostly though its the throwout bearing.

Last edited by bleufiend; Dec 30, 2006 at 07:45 PM.
Reply
Old Dec 31, 2006 | 02:55 AM
  #17  
mistermojorizin's Avatar
mistermojorizin
Registered User
 
Joined: May 2006
Posts: 27
Likes: 0
From: Studio City
Default

try turning off the engine with the clutch pressed down. no rattle.
Reply
Old Dec 31, 2006 | 03:44 PM
  #18  
roast's Avatar
roast
Registered User
iTrader: (2)
 
Joined: Sep 2005
Posts: 4,092
Likes: 1
From: Okay, see?
Default

Originally Posted by bleufiend
Yes and if you understood the operation of it you wouldnt of asked that question.

Its a combination of the throwout bearing/friction disc/pressure plate assembly developing just enough play between each other to cause the rattling. Mostly though its the throwout bearing.
au contraire...

The throwout bearing is what allows the pressure plate to freewheel when the clutch pedal is depressed. This is why your owners manual states not to leave the clutch depressed for extended periods of time. It puts unnecessary wear on the throwout bearing; they are only designed for intermittent use. Although when one starts to go bad, you really only notice it when the clutch is depressed.

Also is what causes the stone grinding sound when the clutch is released and the cars in neutral.
The throwout bearing is not even loaded in that situation. When the clutch is released/engaged the pressure plate is no longer freewheeling thus the bearing is stationary and does not rotate with the pressure plate. The phenomenon you're referring to has to do with the transmission being connected to the idling engine. Even though the tranny is in neutral, since the clutch is engaged, the inner workings of the tranny still have to spin with the engine. Push the clutch in and the noise slows to a halt (the tranny gradually stops spinning). Same concept when you turn the car off in this situation and you get a rattle... it's because the tranny is being brought to a halt with the engine. Push the clutch in to disconnect the tranny from the engine.... no rattle.

Do I clearly not understand the situation?
Reply
Old Dec 31, 2006 | 05:50 PM
  #19  
MR_X's Avatar
MR_X
New Member
iTrader: (5)
 
Joined: Nov 2006
Posts: 3,503
Likes: 0
From: El Centro, Ca.
Default

actually I don't think is the tranny at all. Today I took the exhaust off the car and I had to move the car in the middle of this. I notice that the rattle wasn't there at all without the "y-pipe" back. Unless I have a different rattle.
Reply
Old Jan 1, 2007 | 01:00 AM
  #20  
QuicksilverZ33's Avatar
QuicksilverZ33
Registered User
iTrader: (34)
 
Joined: Nov 2006
Posts: 920
Likes: 1
From: east coast
Default

Originally Posted by MR_X
actually I don't think is the tranny at all. Today I took the exhaust off the car and I had to move the car in the middle of this. I notice that the rattle wasn't there at all without the "y-pipe" back. Unless I have a different rattle.
Mayby the exhaust was too loud for you to hear it...
Reply



All times are GMT -8. The time now is 12:42 AM.