New noise from engine - Fuelly Forums

Android Users - Coming Soon! - Migrating from aCar 4.8 to 5.0

Reply
 
Thread Tools Display Modes
 
Old 12-07-2009, 11:29 AM   #1
Registered Member
 
theholycow's Avatar
 
Join Date: Apr 2008
Posts: 6,624
Country: United States
Send a message via ICQ to theholycow Send a message via AIM to theholycow Send a message via MSN to theholycow Send a message via Yahoo to theholycow
Question New noise from engine

What is that sound? It comes from the engine, follows the engine RPM, comes and goes randomly. It started yesterday after an hour of smooth driving and would go away if I put it in neutral and let it get down to idle. This morning in the cold it did made the noise a lot until it warmed up. It sounds a little rougher in person, but not quite like a plastic gear grinding. Stereo is off and it's definitely not coming from the speakers.

Shorter video where it was recorded better:
[yt]2wShMP9pphs[/yt]

Longer video where you can hear the way it follows engine RPM:
[yt]Zc6BvDff9W8[/yt]
__________________

__________________
This sig may return, some day.
theholycow is offline   Reply With Quote
Old 12-07-2009, 12:34 PM   #2
Registered Member
 
Join Date: Apr 2008
Posts: 1,258
Country: United States
Location: wiliamsburg virigina
Idler bearing
Power steering fluid
Belt tension

Get a mechanics stethoscope (metal tip) and see if you can isolate the sound.

Careful not to stick it in something moving.

regards
Gary
__________________

__________________
R.I.D.E. is offline   Reply With Quote
Old 12-07-2009, 12:47 PM   #3
Registered Member
 
theholycow's Avatar
 
Join Date: Apr 2008
Posts: 6,624
Country: United States
Send a message via ICQ to theholycow Send a message via AIM to theholycow Send a message via MSN to theholycow Send a message via Yahoo to theholycow
Good idea. I'll see if it will make the noise while parked. If so I should be able to find it with the mechanic's stethoscope (I have a decent one).
__________________
This sig may return, some day.
theholycow is offline   Reply With Quote
Old 12-07-2009, 02:22 PM   #4
Site Team / Moderator
 
Jay2TheRescue's Avatar
 
Join Date: Sep 2008
Location: Northern Virginia
Posts: 4,657
Country: United States
Location: Northern Virginia
Yeah, my serpentine belt will make a similar noise (although much quieter) when its really cold outside until it warms up. The belt, tensioner, & idler pulley were replaced at the 150,000 mile service, so they're not that old.
__________________






Jay2TheRescue is offline   Reply With Quote
Old 12-07-2009, 03:37 PM   #5
Registered Member
 
theholycow's Avatar
 
Join Date: Apr 2008
Posts: 6,624
Country: United States
Send a message via ICQ to theholycow Send a message via AIM to theholycow Send a message via MSN to theholycow Send a message via Yahoo to theholycow
Now that you mention it, forever I've had a noise that I attributed to the serpentine belt that happens shortly after starting in the cold, but I've never been able to hear it inside and I don't think it continued while driving...just while idling. It is vaguely similar.

I'd love if it turns out to be the belt and/or idler and/or tensioner.
__________________
This sig may return, some day.
theholycow is offline   Reply With Quote
Old 12-07-2009, 04:02 PM   #6
Registered Member
 
JanGeo's Avatar
 
Join Date: Jan 2006
Posts: 2,442
Country: United States
Send a message via Yahoo to JanGeo
That is a pretty high pitch whine from 1000 - 2000 rpm of engine speed so I would say it would have to be the alternator since everything else turns at a much lower RPM. Something that loud could be the transmission too but more likely the alternator bearings or cooling fan on the alternator. Check for red dust and oil stains on the alternator as well as black belt dust.

I assume you don't have a Supercharger or Turbo in that engine?
JanGeo is offline   Reply With Quote
Old 12-07-2009, 04:26 PM   #7
Registered Member
 
theholycow's Avatar
 
Join Date: Apr 2008
Posts: 6,624
Country: United States
Send a message via ICQ to theholycow Send a message via AIM to theholycow Send a message via MSN to theholycow Send a message via Yahoo to theholycow
Definitely not transmission. It stays with engine RPM even in neutral.

No forced induction.

That's two votes for alternator (one on another forum). I'll be so happy if it turns out to be something easy and inexpensive like all these suggestions.
__________________
This sig may return, some day.
theholycow is offline   Reply With Quote
Old 12-07-2009, 05:29 PM   #8
Registered Member
 
IndyFetch's Avatar
 
Join Date: Nov 2008
Posts: 627
Country: United States
Location: Indianapolis
So that's where my vacuum cleaner went.
IndyFetch is offline   Reply With Quote
Old 12-07-2009, 07:17 PM   #9
Registered Member
 
Join Date: Apr 2008
Posts: 1,258
Country: United States
Location: wiliamsburg virigina
Spray some brake cleaner on the belt and see if it goes away.

regards
Gary
__________________
R.I.D.E. is offline   Reply With Quote
Old 12-07-2009, 07:18 PM   #10
Site Team / Moderator
 
Jay2TheRescue's Avatar
 
Join Date: Sep 2008
Location: Northern Virginia
Posts: 4,657
Country: United States
Location: Northern Virginia
Yeah, I first thought it sounded like turbo whine too, but knowing that he didn't have a turbo I immediately dismissed it.
__________________

__________________






Jay2TheRescue is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Incorrect Milage Calcuatlion PatM Fuelly Web Support and Community News 4 07-17-2009 08:21 PM
ECT Analyzer/manual TC lockup GasSavers_Bruce Transmissions and Running Gear 60 04-01-2008 11:37 AM
How far do you drive daily? OdieTurbo General Fuel Topics 56 03-31-2007 02:49 AM
State of the Union address touches on "oil addiction." Matt Timion General Discussion (Off-Topic) 31 02-06-2006 04:38 PM

Powered by vBadvanced CMPS v3.2.3


All times are GMT -8. The time now is 10:17 PM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.