spark plug on #4 cylider looks bad... why? - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

Bell040 · 06-23-2013, 10:34 PM

I was changing my spark plugs today to the LS7/LS9 plugs (AC Delco 104's).

When I was removing the stock plugs I noticed excessive wear on the spark plug in the #4 cylinder. Like so:

Top = new 104 plug
Middle = old 110 plugs (this one looks similar to the ones from all other cylinders)
Bottom = old 110 plug from cylinder #4 (I am guessing that a .087 gap is bad)

What is causing this?

Info about my car:

-about 140,000 total miles, about 70K of those are on the cam in my sig (all on the same 110 plugs)
-no CEL because of misfire

SPCBA · 06-23-2013, 10:36 PM

looks like the tip failed and it just snowballed. dont see any ash on it just excessive soot

Bell040 · 06-23-2013, 10:42 PM

So .... nothing to worry about?

BLACK10 · 06-23-2013, 10:46 PM

that doesnt look ok to me.........

Bell040 · 06-23-2013, 11:21 PM

Quote:

Originally Posted by BLACK10

that doesnt look ok to me.........

That's what I was thinking, but what is not okay?

Will the new plug fix the problem? ... or is it possible that something is wrong with that cylinder system (injector, valve, leak, etc)?

BLACK10 · 06-23-2013, 11:26 PM

hard to tell from a pic, but looks really black. so how many miles on that plug?

Bell040 · 06-23-2013, 11:36 PM

Quote:

Originally Posted by BLACK10

hard to tell from a pic, but looks really black. so how many miles on that plug?

140,000

SPCBA · 06-24-2013, 12:09 AM

Quote:

Originally Posted by Bell040

So .... nothing to worry about?

i would be really worried. i would check my plugs everyday and take it to my tuner. my tuner wouldnt be ok with it either. something went wrong. hope its a bad plug.

Iam Broke · 06-24-2013, 04:46 AM

Could be some detonation caused that tip to fail sometime along the way, but 140k on a set of plugs? Sheesh. Who knows if or when.

Craig B · 06-24-2013, 05:41 AM

Looks like #4 may be taking on some oil? Could be why the tip is missing, from detonation.

Bell040 · 06-24-2013, 10:40 AM

Quote:

Originally Posted by SPCBA

i would be really worried. i would check my plugs everyday and take it to my tuner. my tuner wouldnt be ok with it either. something went wrong. hope its a bad plug.

I can pull #4 every week or so to check. Every day is not feasible, as life still happens. It is too bad that #4 is by far the hardest plug to pull.

Quote:

Originally Posted by Iam Broke

Could be some detonation caused that tip to fail sometime along the way, but 140k on a set of plugs? Sheesh. Who knows if or when.

I had them out at ~70K (during cam swap) and they were fine.

Quote:

Originally Posted by Criag B

Looks like #4 may be taking on some oil? Could be why the tip is missing, from detonation.

I guess there is no way to check this? ... without pulling the heads anyway

Question is... why was there no CEL due to misfire?

strych9 · 06-24-2013, 10:57 AM

Oil won't make the tip wear away like that. But with 140k, hard to say what's happened there. To me in looks like the ceramic is gone, and that usually happens to to an ultra-lean condition (bad/plugged injector), detonation, or the plug got really hot for some reason.

You don't mention any other underlying symptoms, but I would at the very least run a compression check to make sure all is even. If it's okay, put in your new plugs and see how it runs. If it runs okay, give it some hard pulls and take out #4 and another plug for comparison. If all looks good, put it back together and check that plug occasionally for any abnormalities.

litle88 · 06-24-2013, 11:04 AM

So you've ran a spark plug for a total of 140k miles? Or 70k after the cam?

Either way that's crazy intervals. Your lucky the others don't look the same way.

Southern Comfort · 06-24-2013, 11:20 AM

Is that header tube the same color as the rest?

06-23-2013, 10:34 PM	#1
Bell040 Drives: 2SS/RS - Black - GFX Join Date: Nov 2008 Location: B'ham, Alabama Posts: 2,458 View My Garage	spark plug on #4 cylider looks bad... why? I was changing my spark plugs today to the LS7/LS9 plugs (AC Delco 104's). When I was removing the stock plugs I noticed excessive wear on the spark plug in the #4 cylinder. Like so: Top = new 104 plug Middle = old 110 plugs (this one looks similar to the ones from all other cylinders) Bottom = old 110 plug from cylinder #4 (I am guessing that a .087 gap is bad) What is causing this? Info about my car: -about 140,000 total miles, about 70K of those are on the cam in my sig (all on the same 110 plugs) -no CEL because of misfire __________________ Ordered: 10-13-08 Built: 3-30-09 (#1691) Recieved: 6-12-09 Blacked out, Cammed (Lunati Voodoo 233/245, .578/.598 @114°, +4°), ARH LTs, VR OTR CAI, Cutouts, and lots of other fun mods.

06-23-2013, 10:36 PM	#2
SPCBA Drives: pleather and Chiclets Join Date: Mar 2012 Location: a line somwhere Posts: 4,206 View My Garage	looks like the tip failed and it just snowballed. dont see any ash on it just excessive soot __________________ the power by www.cunningham-motorsports.com the brakes by www.RacingBrake.com

06-23-2013, 10:42 PM	#3
Bell040 Drives: 2SS/RS - Black - GFX Join Date: Nov 2008 Location: B'ham, Alabama Posts: 2,458 View My Garage	So .... nothing to worry about? __________________ Ordered: 10-13-08 Built: 3-30-09 (#1691) Recieved: 6-12-09 Blacked out, Cammed (Lunati Voodoo 233/245, .578/.598 @114°, +4°), ARH LTs, VR OTR CAI, Cutouts, and lots of other fun mods.

06-24-2013, 04:46 AM	#9
Iam Broke PHAT B33 Drives: 2012 TF3 Camaro 2SS/RS M6 Join Date: Jun 2012 Location: Dark of the Moon Posts: 1,460 View My Garage	Could be some detonation caused that tip to fail sometime along the way, but 140k on a set of plugs? Sheesh. Who knows if or when. __________________ Another 1 of 371 '12 T3 LS3 M6's built.

06-24-2013, 10:57 AM	#12
strych9 I'll be back... Drives: Subaru, HD Road Glide Special Join Date: Apr 2012 Location: Omaha, NE Posts: 3,036 View My Garage	Oil won't make the tip wear away like that. But with 140k, hard to say what's happened there. To me in looks like the ceramic is gone, and that usually happens to to an ultra-lean condition (bad/plugged injector), detonation, or the plug got really hot for some reason. You don't mention any other underlying symptoms, but I would at the very least run a compression check to make sure all is even. If it's okay, put in your new plugs and see how it runs. If it runs okay, give it some hard pulls and take out #4 and another plug for comparison. If all looks good, put it back together and check that plug occasionally for any abnormalities. __________________ Bye bye, Bumblebee! --------------------------------------------------------------------------------------- Build Journal My Garage GoPro Mic Hack

06-23-2013, 10:46 PM	#4
BLACK10 Drives: 2010 CAMARO. 10.04@133mph, 1.4 60' Join Date: Jul 2009 Location: Lafayette, Louisiana Posts: 4,585	that doesnt look ok to me.........

06-23-2013, 11:26 PM	#6
BLACK10 Drives: 2010 CAMARO. 10.04@133mph, 1.4 60' Join Date: Jul 2009 Location: Lafayette, Louisiana Posts: 4,585	hard to tell from a pic, but looks really black. so how many miles on that plug?

06-24-2013, 05:41 AM	#10
Craig B Drives: 2013 1LE Join Date: May 2013 Location: NJ Posts: 685	Looks like #4 may be taking on some oil? Could be why the tip is missing, from detonation.

06-24-2013, 11:04 AM	#13
litle88 V8 Lounge member #2 Drives: 2001 Ws6 Join Date: Sep 2009 Location: Burbank,IL Posts: 6,373	So you've ran a spark plug for a total of 140k miles? Or 70k after the cam? Either way that's crazy intervals. Your lucky the others don't look the same way. __________________ 2001 ws6, 40k miles, Ls3 416 stroker, short block built by PER the rest by me. LPE Ls3 heads milled to 12-1 comp, FAST 102, NW 102, kooks 2", dual DMH cutouts, Magnaflow C/B, BTR cam + springs. Full UMI suspension.

06-24-2013, 11:20 AM	#14
Southern Comfort No Tags/Habitual Violator Drives: 2012 SIM 2SS/RS & z71 Join Date: Sep 2011 Location: North Georgia Posts: 2,379 View My Garage	Is that header tube the same color as the rest?