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.

Engine tapping...?

Thread Tools
 
Search this Thread
 
Old 12-29-2006, 03:43 PM
  #1  
Senior Member
Posts like a Turbo
Thread Starter
 
zuper8's Avatar
 
Join Date: Oct 2006
Posts: 441
Likes: 0
Received 0 Likes on 0 Posts
zuper8 is on a distinguished road
Default Engine tapping...?

Whenever I start my parent'* 96 SE (home for break), for maybe the first 30 seconds I hear this rattling, kind of tapping noise from the engine. I'm REALLY sorry I can't be more specific, but I don't know how else to describe it! Just, uh, tapping. It'* very strange, AND the check engine light has been on for the past few days, so I'm figuring something'* going to go wrong really soon...
Old 12-29-2006, 03:44 PM
  #2  
Senior Member
Posts like a Turbo
Thread Starter
 
zuper8's Avatar
 
Join Date: Oct 2006
Posts: 441
Likes: 0
Received 0 Likes on 0 Posts
zuper8 is on a distinguished road
Default

Crap I ALWAYS post on the wrong board, this should totally be in mechanical 96-99
Old 12-29-2006, 03:47 PM
  #3  
Junior Member
Posts like a Ricer Type-R
 
willwren's Avatar
 
Join Date: Aug 2002
Posts: 11
Likes: 0
Received 4 Likes on 4 Posts
willwren is on a distinguished road
Default

Next time you hear it, pop the hood and feel the evap purge solonoid bolted to a bracket on your front valve cover. You'll need the engine cover off in advance.

In cold weather the evap purge is much more obvious, and we get countless reports of mysterious ticking. It'* normal for it to go through a purge cycle on startup.

Make sure that'* the sound (you'll feel it), or see if it'* actually something else.
Old 12-29-2006, 03:50 PM
  #4  
Junior Member
Posts like a Ricer Type-R
 
willwren's Avatar
 
Join Date: Aug 2002
Posts: 11
Likes: 0
Received 4 Likes on 4 Posts
willwren is on a distinguished road
Default

For the record, the solonoid on the 92-95 cars is on the evap canister under the airbox. On 96-current, it'* where I mentioned in the post above.
Old 12-29-2006, 07:27 PM
  #5  
Senior Member
True Car Nut
 
bill buttermore's Avatar
 
Join Date: Mar 2004
Location: Ames, Iowa
Posts: 3,066
Likes: 0
Received 3 Likes on 3 Posts
bill buttermore is on a distinguished road
Default

Does the tapping kinda go along with the speed of the engine? If so, it might just be a lifter that takes a few seconds to pump up with oil before it operates quietly. That would be pretty common and nothing to worry about at all. Still, check your oil to make sure the level is up. Low oil level can cause all kinds of valve train noises.
Old 12-29-2006, 10:28 PM
  #6  
Senior Member
Posts like a Northstar
 
F14CRAZY's Avatar
 
Join Date: Apr 2006
Location: Dimondale, MI
Posts: 549
Likes: 0
Received 0 Likes on 0 Posts
F14CRAZY is on a distinguished road
Default

I'd inspect the harmonic balancer (crankshaft pulley). See if the rubber on its face is in good shape. When they go bad, the rubber may look torn up and cause a noise. This one tends to happen at idle but go away with RPM
Old 12-29-2006, 10:35 PM
  #7  
Senior Member
Certified GM nut
 
Technical Ted's Avatar
 
Join Date: Oct 2005
Location: Western New York
Posts: 1,942
Likes: 0
Received 0 Likes on 0 Posts
Technical Ted is on a distinguished road
Default

Get it scanned & let'* see what the code is. The sooner you get it done the better, tow trucks are expensive.
Old 12-29-2006, 10:38 PM
  #8  
Junior Member
Posts like a Ricer Type-R
 
willwren's Avatar
 
Join Date: Aug 2002
Posts: 11
Likes: 0
Received 4 Likes on 4 Posts
willwren is on a distinguished road
Default

Originally Posted by F14CRAZY
I'd inspect the harmonic balancer (crankshaft pulley). See if the rubber on its face is in good shape. When they go bad, the rubber may look torn up and cause a noise. This one tends to happen at idle but go away with RPM
Failing harmonic balancers don't 'tap'. They CLATTER horribly. Iron on Iron. And the sound does not go away based on temperature or time.
Old 12-30-2006, 12:01 AM
  #9  
Member
Posts like a V-Tak
 
ManMan inc's Avatar
 
Join Date: Sep 2006
Location: Union, New Jersey
Posts: 37
Likes: 0
Received 0 Likes on 0 Posts
ManMan inc is on a distinguished road
Default

Originally Posted by willwren
Originally Posted by F14CRAZY
I'd inspect the harmonic balancer (crankshaft pulley). See if the rubber on its face is in good shape. When they go bad, the rubber may look torn up and cause a noise. This one tends to happen at idle but go away with RPM
Failing harmonic balancers don't 'tap'. They CLATTER horribly. Iron on Iron. And the sound does not go away based on temperature or time.
Yea that happened to me, not good, definitely not the balancer if its just tapping. Oh the flashbacks...Horrible Clattering, AHHH!
Old 12-30-2006, 01:58 AM
  #10  
Senior Member
Posts like a Northstar
 
F14CRAZY's Avatar
 
Join Date: Apr 2006
Location: Dimondale, MI
Posts: 549
Likes: 0
Received 0 Likes on 0 Posts
F14CRAZY is on a distinguished road
Default

I agree a HB is more or a "clatter" than a "tap" but we cannot hear this engine over a message board (no sound or vid clip ), and the fact that people describe sounds differently than others. Just a possibility I wanted to put out there.


Quick Reply: Engine tapping...?



All times are GMT -4. The time now is 02:44 AM.