Read My Plugs Please
08-17-2015, 08:12 PM
#1
Melting Slicks
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Read My Plugs Please
I got around to changing out my plugs and I'd like your help reading them. This is what they look like after about 40k miles(I know too long). Anything I should be concerned about? Pay particular attention to plug #3.
Sorry the lighting looked better in the garage.
Now this is new plug #3 after maybe a couple hundred miles.
While the rest look similar to this.
Coincidentally, or maybe not, the noise I have been chasing which I assumed was an exhaust leak, is most noticeable right around plug #3.
2007 LS2 with H/C/FAST, NGK TR55s .048ish and slightly bumped CR. Always ran on 93.
So talk to me. What do you think is going on and what do I need to be worried about? The car runs great and no codes are stored or being thrown.
One of my posts from the exhaust leak thread.
Thanks
Sorry the lighting looked better in the garage.
Now this is new plug #3 after maybe a couple hundred miles.
While the rest look similar to this.
Coincidentally, or maybe not, the noise I have been chasing which I assumed was an exhaust leak, is most noticeable right around plug #3.
2007 LS2 with H/C/FAST, NGK TR55s .048ish and slightly bumped CR. Always ran on 93.
So talk to me. What do you think is going on and what do I need to be worried about? The car runs great and no codes are stored or being thrown.
One of my posts from the exhaust leak thread.
Any update on this? It sounds very similar to what I have been experiencing. My sound is on the front driver's side and only during throttle. If I put the trans in neutral while rolling the sound is not present until I step on the throttle. In gear it is only present while accelerating as well. There is also no rhythm to the sound. This leads me to believe it is an exhaust leak. If there was something in the tire/wheel it would only make the sound during a revolution and you would almost be able to time the beat as you memorize the rate of rotation. Valvetrain noises also have somewhat of a rhythm as well since everything moves in unison. This sound just seems to be sporadic. My header bolts feel tight and so do the connections down stream so I would have to assume it's the header gasket?
H/C/FAST Kooks w/cats and Borla.
H/C/FAST Kooks w/cats and Borla.
Thanks
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zrracer (10-13-2015)
08-17-2015, 09:27 PM
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St. Jude Donor '13-'14-'15
Reading plugs is generally used in racing to determine either timing or fuel mixture---But that can only be done on a NEW set
On your plugs they are far too old to read for that
However you are correct that #3 looks bad---on both sets---
If you aren't getting a misfire code or can hear a misfire then I would suspect a broken valve spring or something related to the valve train on #3
If you do hear a misfire then most likely it's the plug wire or unlikely maybe the coil or
lastly a bad injector---
On your plugs they are far too old to read for that
However you are correct that #3 looks bad---on both sets---
If you aren't getting a misfire code or can hear a misfire then I would suspect a broken valve spring or something related to the valve train on #3
If you do hear a misfire then most likely it's the plug wire or unlikely maybe the coil or
lastly a bad injector---
08-17-2015, 10:25 PM
#3
Melting Slicks
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Reading plugs is generally used in racing to determine either timing or fuel mixture---But that can only be done on a NEW set
On your plugs they are far too old to read for that
However you are correct that #3 looks bad---on both sets---
If you aren't getting a misfire code or can hear a misfire then I would suspect a broken valve spring or something related to the valve train on #3
If you do hear a misfire then most likely it's the plug wire or unlikely maybe the coil or
lastly a bad injector---
On your plugs they are far too old to read for that
However you are correct that #3 looks bad---on both sets---
If you aren't getting a misfire code or can hear a misfire then I would suspect a broken valve spring or something related to the valve train on #3
If you do hear a misfire then most likely it's the plug wire or unlikely maybe the coil or
lastly a bad injector---
08-18-2015, 02:24 AM
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St. Jude Donor '13-'14-'15
A valve seal could cause oil in the combustion chamber But usually if one is bad they all are bad------
Since you are hearing a noise I think more now it can be a broken spring-----
A broken spring can take out the seal too
ALSO Is the plug oil fouled or fuel fouled do you think ??
Typically if you lave a plug out into the air for a few hours if it is fuel fouled it will dry out and look just like black dry soot--Whereas an oil fouled plug will stay oily always--
Since you are hearing a noise I think more now it can be a broken spring-----
A broken spring can take out the seal too
ALSO Is the plug oil fouled or fuel fouled do you think ??
Typically if you lave a plug out into the air for a few hours if it is fuel fouled it will dry out and look just like black dry soot--Whereas an oil fouled plug will stay oily always--
08-18-2015, 09:05 AM
#5
Melting Slicks
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A valve seal could cause oil in the combustion chamber But usually if one is bad they all are bad------
Since you are hearing a noise I think more now it can be a broken spring-----
A broken spring can take out the seal too
ALSO Is the plug oil fouled or fuel fouled do you think ??
Typically if you lave a plug out into the air for a few hours if it is fuel fouled it will dry out and look just like black dry soot--Whereas an oil fouled plug will stay oily always--
Since you are hearing a noise I think more now it can be a broken spring-----
A broken spring can take out the seal too
ALSO Is the plug oil fouled or fuel fouled do you think ??
Typically if you lave a plug out into the air for a few hours if it is fuel fouled it will dry out and look just like black dry soot--Whereas an oil fouled plug will stay oily always--
The noise isn't constant. Only during light to moderate throttle and it has no rythem. Wouldn't a broken spring make noise all the time?
I was listening to some soundclips of broken springs and mine does not sound like that.
Last edited by 5knives; 08-18-2015 at 12:13 PM.
08-18-2015, 03:03 PM
#6
Melting Slicks
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So I pulled the plug again, the car hadn't been driven since the picture, and the plug is dry now. I started the car and let it run for about a minute. Then I revved it up until I heard the noise and let it sit there for a few seconds. I did this a few times then shut it down and pulled the plug again. It's still dry and almost looks as if it was cleaned off slightly. It's cleaner than in the original picture but not like the others. I'm sure if I was out for a longer drive the plug would get wet and dark again. Does any of that information help?
08-19-2015, 02:53 AM
#7
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St. Jude Donor '13-'14-'15
Impossible to diagnose deeply without having the car here---A broken spring actually would be louder at low RPM's'--
Sorry to say it's either time to take it to a shop or pull the valve cover off on the driver's side----I would NOT drive the car though very much because if indeed there is something amiss in the valve train--It could eventually break something else and become catastrophic----
Sorry to say it's either time to take it to a shop or pull the valve cover off on the driver's side----I would NOT drive the car though very much because if indeed there is something amiss in the valve train--It could eventually break something else and become catastrophic----