Were these plugs run to lean?

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Pulled these plugs out of my TransAm today. The plug on the left was pulled out of the passenger side. All 4 plugs looked like that one. The plug on the right was pulled out of the driver side. All 4 plugs looked the same. I'm thinking yellow electrode and bright white ceramic are not good. I'm thinking my o2 sensor is whacked out but isn't throwing a code. There is no other sensor in the car that could have such an effect on only 1 bank of cylinders. Sound reasonable?
 
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it almost looks like deposits from fuel additives or from the fuel itself.... do you add anything to your tank? are they the correct plugs? maybe running a little hot?
 

MiniTransAm

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nothing added to the tank. Did go drag racing last friday. Plugs were not wet when I pulled them out. They aren't the factory recommended plugs. These are what alot of guys on LS1 tech run. I replaced these with regular stock AC-Delco's
 
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My '07 Dodge Dakota looked exactly like those plugs. They are the factory plugs and they were worn out at 30,000 miles and had a greenish/yellowish deposit at the tip of the ceramic and the rest of the ceramic was white like yours. For kicks I checked the gap on the used plugs..they were at .050 so it lost .010 in 30,000 miles.
 
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Not a thing wrong with those plugs. Reading plugs on a street driven vehicle is about fruitless, and can only indicate really bad problems. Not knowing the gas additives in your gas throws curves as well.
 

MiniTransAm

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It's just weird to me that only one bank of plugs looked this way. The other bank looked fine. Either way, they got replaced with AC-delco stockers and I replaced both O2 sensors. Car seems to run much better now. I may pull those driver side plugs in a thousand miles or so and see how they look.
 

OVERKILL

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They look fine. Remember, computer controlled engines will intentionally run quite lean under low or no load to keep emissions down and keep the plugs clean.
 
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Read punisher's comments. Plugs are not read on the tip of the insulator for mixture. There is an annular ring near the base that an be read after a full throttle 'cut clean' situation. Well, OK... a really rich mixture will make the plug black. Today's fuels don't read well. All you can really tell is if the heat range if OK, in reality. Maybe additive deposits.
 
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Read this a second time...you mean all four plugs in each bank looked the same? They should be more uniform I would think. Maybe on bank is running leanner if thats possible?
 

MiniTransAm

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 Originally Posted By: Bluestream
Read this a second time...you mean all four plugs in each bank looked the same? They should be more uniform I would think. Maybe on bank is running leanner if thats possible?
Correct. The driver side plugs all looked the yellow plug. The passenger side plugs all looked like the other one. I have replaced all the plugs with stock ACDelco irridium plugs gapped at 040. I also replaced both pre cat o2 sensors. I had been getting a periodic CEL for one of the o2 sensors. There is only 1 sensor that controls the A/F for each bank of cylinders and that's the o2 sensor. After I changed them out we just took it down to the beach which is a 4 hour trip. Car performed flawless. Probably the best it's run since I've owned it. I think after 1000 miles I'll pull a plug from each side and see how they look. My guess is that the problem has been fixed.
 

MiniTransAm

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 Originally Posted By: Bluestream
The plugs look fine. The fingers could use a cleaning though...
LOL, yeah they got a good scrub :-D
 
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