Welcome to the North American Subaru Impreza Owners Club Monday December 22, 2014
Home Forums WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
Here you can view your subscribed threads, work with private messages and edit your profile and preferences Home Registration is free! Visit the NASIOC Store NASIOC Rules Search Find other members Frequently Asked Questions Calendar Archive NASIOC Upgrade Garage Logout
Go Back   NASIOC > NASIOC Technical > Normally Aspirated Powertrain

Welcome to NASIOC - The world's largest online community for Subaru enthusiasts!
Welcome to the NASIOC.com Subaru forum.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, free of charge, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join our community today!

If you have any problems with the registration process or your account login, please contact us.
* Registered users of the site do not see these ads.
Reply
 
Thread Tools Display Modes
Old 11-06-2006, 03:28 PM   #1
HamFist
Scooby Specialist
 
Member#: 2112
Join Date: Aug 2000
Chapter/Region: MWSOC
Vehicle:
2000 Impreza 2.5RS
BRP

Default Your car is warmed up and you let it idle for a long time: What's that damn knock?

Like the long title says:

What's that knock from the engine after it idles for a long time (5 minutes)? I figure on replacing EVERYTHING in my shortblock just to be on the safe side. I've heard of other scoobs doing this and it's normal. The "normal" part is what I don't believe. However, it did run like a champ the whole time, so I'm hard pressed to say anything was wrong. It was totally random and my car didn't consume any oil. Was it the timing belt tensioner?

<---confuzzled. His car is in pieces and he's looking for an excuse to upgrade everything
* Registered users of the site do not see these ads.
HamFist is offline   Reply With Quote
Old 11-06-2006, 03:47 PM   #2
atech_rallyrs
Scooby Specialist
 
Member#: 116638
Join Date: Jun 2006
Chapter/Region: MAIC
Vehicle:
00 impreza naSTi
el typico silver

Default

Its your car requesting to have everything upgraded.
atech_rallyrs is offline   Reply With Quote
Old 11-06-2006, 04:06 PM   #3
b4wantab
Scooby Specialist
 
Member#: 21293
Join Date: Jul 2002
Chapter/Region: MWSOC
Location: Oak Park, IL
Vehicle:
05 OB Black Bean
1969 W-30

Default

Don't really know, however I had a wrist pin freeze and shatter the piston once. Not a subbie engine, but I would get this light knock on and off. Too deep for a lifter but too light for a connecting rod. Anyway when it finnally went it took the block with it.

If you got it apart check them out.

Peace,

Greg
b4wantab is offline   Reply With Quote
Old 11-06-2006, 05:58 PM   #4
protocall
Scooby Newbie
 
Member#: 38348
Join Date: Jun 2003
Chapter/Region: NESIC
Location: Fitchburg
Default

My moms 2002 forester knocked when cold. I told her it was normal. She took it to a dealer anyways. They replaced one cylinder and head gaskets under warranty. I don't know how that makes any sense, but the car never knocked again and drove much, much smoother
protocall is offline   Reply With Quote
Old 11-06-2006, 06:48 PM   #5
8Complex

Moderator
 
Member#: 922
Join Date: Feb 2000
Chapter/Region: MWSOC
Location: Schaumburg, IL
Vehicle:
04 FXT
Red

Default

I'd check the tensioner, as well as the idler pulleys for the timing belt.
8Complex is offline   Reply With Quote
Old 11-08-2006, 01:17 AM   #6
kavy
Scooby Newbie
 
Member#: 124824
Join Date: Sep 2006
Chapter/Region: W. Canada
Location: Calgary, Canada
Vehicle:
07 Impreza
CGM

Default

normal,
lifter tick happens to all vehicles boxer's are just louder.
kavy is offline   Reply With Quote
Old 11-08-2006, 11:44 AM   #7
HamFist
Scooby Specialist
 
Member#: 2112
Join Date: Aug 2000
Chapter/Region: MWSOC
Vehicle:
2000 Impreza 2.5RS
BRP

Default

My SOHC doesn't have lifters. The DOHC have buckets, is that what you mean? That doesn't explain my occasional knock like this. I'm tearing down the motor and it's almost out. I didn't know what I might look for aside from any bearings that might be fried.
HamFist is offline   Reply With Quote
Old 11-09-2006, 10:25 AM   #8
GreenMarine
Scooby Guru
 
Member#: 36080
Join Date: Apr 2003
Chapter/Region: South East
Default

Quote:
Originally Posted by protocall View Post
My moms 2002 forester knocked when cold. I told her it was normal. She took it to a dealer anyways. They replaced one cylinder and head gaskets under warranty. I don't know how that makes any sense, but the car never knocked again and drove much, much smoother
If you can tell me how they "replaced one cylinder" that would be great... Never heard of people replacing cylinders in engines (other than old Aircraft engines)...
GreenMarine is offline   Reply With Quote
Old 11-09-2006, 10:48 AM   #9
protocall
Scooby Newbie
 
Member#: 38348
Join Date: Jun 2003
Chapter/Region: NESIC
Location: Fitchburg
Default

Quote:
Originally Posted by GreenMarineSVX View Post
If you can tell me how they "replaced one cylinder" that would be great... Never heard of people replacing cylinders in engines (other than old Aircraft engines)...
Sorry man don't know the details. This was over a year ago. I got the info through my mom which probably isn't the most reliable. Could it have just been one cylinder head?
The point of my post though was that I don't think the knocking is always normal. Her car knocked the same why mine did when it was cold. After the service it no longer did that. And it drove smoother and stronger.
protocall is offline   Reply With Quote
Old 11-09-2006, 12:53 PM   #10
wagonman
Scooby Specialist
 
Member#: 971
Join Date: Feb 2000
Chapter/Region: South East
Location: Morganton, NC
Default

I would say piston slap, but if it does it when its warm....I would lean towards the normal Subaru valve ticking.

My 93 did it until we sold it with 184,000 miles on it, and my 00' RS does the same thing.
wagonman is offline   Reply With Quote
Old 11-09-2006, 01:55 PM   #11
Hayes
Scooby Specialist
 
Member#: 11808
Join Date: Oct 2001
Location: Cape Coral,FL
Default

I'm with 8complex, as a possible cause is the timing belt tenioner
Hayes 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
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Mechanical Engine Knock After Car Is Warmed Up buzz313th Factory 2.0L Turbo Powertrain (EJ Series Factory 2.0L Turbo) 7 04-26-2013 10:10 AM
Cold Startup: How Long Do You Let It Idle? bnr34rb26dett General Community 58 11-17-2008 03:33 AM
If your car is towed how would you know where it went? -=C=- Off-Topic 6 04-24-2007 10:56 PM
Why do I smell gas when the car is warming up? BangWRX Factory 2.0L Turbo Powertrain (EJ Series Factory 2.0L Turbo) 21 02-18-2007 09:25 AM
CAR is back up and running insane. AHAH sad turbo civic tried to race me! AWJunkies Southern California Impreza Club Forum -- SCIC 2 07-26-2003 02:13 AM


All times are GMT -4. The time now is 07:48 PM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2014 Axivo Inc.
Copyright ©1999 - 2014, North American Subaru Impreza Owners Club, Inc.