knock knock knock - GM Forum - Buick, Cadillac, Chev, Olds, GMC & Pontiac chat


1992-1999 Series I L27 (1992-1994 SE,SLE, SSE) & Series II L36 (1995-1999 SE, SSE, SLE) and common problems for the Series I and II L67 (all supercharged models 92-99) Including Olds 88's, Olds LSS's and Buick Lesabres Please use General Chat for non-mechanical issues, and Performance and Brainstorming for improvements.

Reply
 
 
 
Thread Tools Search this Thread
Old 09-17-2004, 09:36 AM   #1
Senior Member
True Car Nut
Thread Starter
 
Join Date: May 2003
Location: Grand Rapids, Mi
Posts: 3,244
Thanks: 0
Thanked 0 Times in 0 Posts
L27Buick is on a distinguished road
Default knock knock knock

im hearing a slight knock at the botton of my engine and is their a way i an tell ifs its a normal or bad knock? its not hard knockits a soft knock but it sounds like metal hitting metal.

i found this on a website that list common problema of 3800 Engine noise: Bearing knock was common on many 3.3- and 3.8-liter engines due to too much clearance on the No. 1 main bearing. (1992-94)
could this be my problem my dad had the same thought also.
L27Buick is offline   Reply With Quote
Old 09-17-2004, 12:19 PM   #2
Senior Member
Posts like a Camaro
 
Join Date: Jan 2004
Posts: 1,166
Thanks: 0
Thanked 1 Time in 1 Post
mkaake is on a distinguished road
Default

well i hate to put it this way, but you'll know if it'* a good knock or a bad one soon enough...
mkaake is offline   Reply With Quote
Old 09-17-2004, 12:25 PM   #3
Senior Member
Certified GM nut
 
Join Date: Feb 2003
Location: Georgia
Posts: 2,095
Thanks: 0
Thanked 0 Times in 0 Posts
DrJay is on a distinguished road
Default

I dunno about common, only people I've heard of having it are ones that don't do regular maintenance and people with CRAPPY MECHANICS!!!!! haha..ok..I'm ok...

The quick and nasty way of telling if its rod knock is to take it up to about 2500rpm and do a VERY quick 1/2 throttle jump. If you hear a knock when you do it thats it. It'll sometimes also show its nasty face when driving with light throttle above 2500rpm.

If its something in the valvetrain it'll usually go away above about 1500rpm. If its only there, or loudest, when cold it may just be pistons slap which is the only "normal" knocking noise I can think of.
DrJay is offline   Reply With Quote
Old 09-17-2004, 12:25 PM   #4
Sol
Senior Member
True Car Nut
 
Join Date: Sep 2002
Posts: 8,909
Thanks: 0
Thanked 0 Times in 0 Posts
Sol is on a distinguished road
Default

This happened to a friend of mine last year with a 91 Olds with the 3.8. It was ignored, and it ended up busting a rod. I would get that looked at.
Sol is offline   Reply With Quote
Old 09-17-2004, 01:30 PM   #5
Senior Member
Certified GM nut
 
Join Date: Apr 2003
Location: Davison,Michigan
Posts: 1,867
Thanks: 0
Thanked 0 Times in 0 Posts
russianpolarbear is on a distinguished road
Default

Run some Marvels Magic Oil in your crank next change.
russianpolarbear is offline   Reply With Quote
Old 09-17-2004, 02:28 PM   #6
Senior Member
True Car Nut
Thread Starter
 
Join Date: May 2003
Location: Grand Rapids, Mi
Posts: 3,244
Thanks: 0
Thanked 0 Times in 0 Posts
L27Buick is on a distinguished road
Default

i can only hear it when im at a idel. the car isnt ignorred i ues mobil oil changed every 3000 miles it comes and goes. i know for fact i have a lifter knock but its done it since before i bought the car so i cant tell how long its been doing it.
L27Buick is offline   Reply With Quote
Old 09-17-2004, 03:10 PM   #7
Senior Member
Certified GM nut
 
Join Date: Feb 2003
Location: Georgia
Posts: 2,095
Thanks: 0
Thanked 0 Times in 0 Posts
DrJay is on a distinguished road
Default

cool..how'd ya figure it out?
DrJay is offline   Reply With Quote
Old 09-17-2004, 04:23 PM   #8
Junior Member
Posts like a Ricer Type-R
 
Join Date: Aug 2002
Posts: 10
Thanks: 0
Thanked 0 Times in 0 Posts
willwren is on a distinguished road
Default

Pull your accessory belt, and run the car for a few seconds (no water pump, so don't run over a minute or so). If the sound is gone, look at your harmonic balancer.

Use a stethescope to narrow it down if that test doesn't work.
willwren is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
Knock-knock--- w/ video SUPRCHRGD 1992-1999 12 09-05-2006 10:52 AM
Knock Knock continued (spun bearing) Spiral 1992-1999 5 05-25-2004 09:57 AM
Knock Knock, engine knock? Spiral 1992-1999 5 05-23-2004 10:08 PM
KR without Knock> Not even false knock? streetracer Performance, Brainstorming & Tuning 1 08-18-2003 02:08 PM
Knock Knock Tamara 1992-1999 11 01-31-2003 05:26 PM


Thread Tools Search this Thread
Search this Thread:

Advanced Search

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



All times are GMT -4. The time now is 12:36 PM.


We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.