Read My Plugs Please
Thread Starter
Melting Slicks
Joined: Nov 2010
Posts: 2,626
Likes: 195
From: On the east coast we drive until we die
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
Burning Brakes
Joined: Nov 2010
Posts: 1,008
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From: The only state to ever kick another country's ass! TEXAS
It's really hard to tell from the pics. Looks like you might have a valve stem seal leaking a little or an injector. Hard to tell if it's oil or not. Probably not blowby since it's only one plug. How many miles are on the car?
Thread Starter
Melting Slicks
Joined: Nov 2010
Posts: 2,626
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From: On the east coast we drive until we die
56k on the car and about 40k on the plugs in the top pic. The pics of the single plugs are only about 100 miles or so. Do you think this could be contributing to the noise or vise versa?
Racer
Joined: Sep 2007
Posts: 352
Likes: 29
From: Peoria Arizona
Hard to tell if the black deposits on #3 plug is "dry" or "wet". If the deposits are "dry" you're getting too much fuel, if they are "wet" then you have a problem with oil getting into the cylinder.
Burning Brakes
Joined: Nov 2010
Posts: 1,008
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From: The only state to ever kick another country's ass! TEXAS
Just guessing, I would say the noise is unrelated, unless you are getting a ping in that cylinder from oil in the combustion chamber. You really don't have that many miles on the car. I would guess a valve stem seal, but that's just a guess. That plug looks wet to me, all the way to the seat. Is it wet or dry?
Last edited by Xtremespeed; Aug 17, 2015 at 09:52 PM.
Burning Brakes
Joined: Nov 2010
Posts: 1,008
Likes: 12
From: The only state to ever kick another country's ass! TEXAS
Obviously something isn't right. I would probably start with a compression check and a leakdown test just to verify everything. They are relatively easy, and will keep you from chasing your tail.
Thread Starter
Melting Slicks
Joined: Nov 2010
Posts: 2,626
Likes: 195
From: On the east coast we drive until we die
The plug is wet. I'm hearing a noise which I assumed was an exhaust leak up until now. After seeing this I have to assume it's a misfire/ping from oil in the chamber? But I'm still not getting any codes. I'm guessing I have to bring it to a shop for a compression/leakdown test?
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Melting Slicks
Joined: Jun 2006
Posts: 2,500
Likes: 261
From: Miami Florida
The plug is wet. I'm hearing a noise which I assumed was an exhaust leak up until now. After seeing this I have to assume it's a misfire/ping from oil in the chamber? But I'm still not getting any codes. I'm guessing I have to bring it to a shop for a compression/leakdown test?
As for your spark plugs install new ones and run them for 500 miles then check the new plugs instead.
Thread Starter
Melting Slicks
Joined: Nov 2010
Posts: 2,626
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From: On the east coast we drive until we die
You should check exhaust manifold bolts see if they are all tight cause a couple of loose bolts will cause a leak and in turn the ECM will read one bank leaner than the other adding or taking fuel, I seen as much as 10% leaner on one bank than the other as a result.
As for your spark plugs install new ones and run them for 500 miles then check the new plugs instead.
As for your spark plugs install new ones and run them for 500 miles then check the new plugs instead.
The plugs are brand new, maybe 100+ miles on them. (Not the top pic)
Team Owner
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St. Jude Donor '15
"In honor of jpee"
Thread Starter
Melting Slicks
Joined: Nov 2010
Posts: 2,626
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From: On the east coast we drive until we die
So I pulled the plug again, the car hadn't been driven since the picture, and the plug is dry now. Whatever was on there evaporated (gas vs oil?) 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?
Burning Brakes
Joined: Nov 2010
Posts: 1,008
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From: The only state to ever kick another country's ass! TEXAS
I would say if the plug is dry and doesn't have an oil residue on it, more than likely you have a leaky injector, but the noise you are hearing is throwing me off. Is it a metallic sound and does it speed up and slow down with rpm? Can you hear it at the exhaust tip?
Thread Starter
Melting Slicks
Joined: Nov 2010
Posts: 2,626
Likes: 195
From: On the east coast we drive until we die
I would say if the plug is dry and doesn't have an oil residue on it, more than likely you have a leaky injector, but the noise you are hearing is throwing me off. Is it a metallic sound and does it speed up and slow down with rpm? Can you hear it at the exhaust tip?
Last edited by 5knives; Aug 18, 2015 at 05:42 PM.
Burning Brakes
Joined: Nov 2010
Posts: 1,008
Likes: 12
From: The only state to ever kick another country's ass! TEXAS
It could be the catalytic converter rattling, but it's impossible to say. I would do a compression check and leakdown test if you have the tools and ability. If not, I would take it to someone. I'd love to help more, but I just can't offer much without seeing and hearing in person.
Thread Starter
Melting Slicks
Joined: Nov 2010
Posts: 2,626
Likes: 195
From: On the east coast we drive until we die
It could be the catalytic converter rattling, but it's impossible to say. I would do a compression check and leakdown test if you have the tools and ability. If not, I would take it to someone. I'd love to help more, but I just can't offer much without seeing and hearing in person.
The fact there is no misfire or negative impact on driving performance is throwing me off.
We shall see....
Burning Brakes
Joined: Nov 2010
Posts: 1,008
Likes: 12
From: The only state to ever kick another country's ass! TEXAS
That's a good thing. Even if the noise is exhaust related, it shouldn't contribute to the spark plug condition though. That's why I suggested the compression and leakdown tests. I still think the plug looks like the #3 injector is leaking if that's not oil on it. That would be an easy and relatively inexpensive fix also.
Thread Starter
Melting Slicks
Joined: Nov 2010
Posts: 2,626
Likes: 195
From: On the east coast we drive until we die
The wires are brand new Acdelcos and the sound was there before and after so I don't think it's that. The sound is more like a crackling than a steady tick.
Last edited by 5knives; Aug 18, 2015 at 10:44 PM.
