School me's on spark plug reading.

[Thirdgen89GTA]

I've seen the pictures and googled all the things. But didn't see any pictures that quite match this plug. I need to pull the other 7 and see if they are all the same.

But, so the ring is black with burnt fuel, and the porceline is white as can be, nearly new looking. But there is a white ash on the electrode, fairly uniform coverage.

I installed the plugs about two weeks ago because the old ones looked glazed. These have about 200-300 miles on them.

Thoughts? Normal, or should I look into a colder plug? Is the ash from too much heat?

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[OffshoreDrilling]

reading plugs needs to be done after the condition you're trying to analyze. If you're trying to see if you're running lean at WOT, you've got to shut the car down immediately after a pass and read them. Driving around afterward is going to muck up the plug.

 

[Thirdgen89GTA]

reading plugs needs to be done after the condition you're trying to analyze. If you're trying to see if you're running lean at WOT, you've got to shut the car down immediately after a pass and read them. Driving around afterward is going to muck up the plug.

Yeah, but you can usually tell if something is grossly off. This is just around town driving. I haven't done any kind of real pull on this engine thats lasted more than 5-7 seconds I don't think. Haven't been in any safe place to really do that.

I know the tune is off, I've just never seen a plug with the white ash on the electrode, and the black carbon at the same time. Once the car cools down i'm going to pull the rest of them. Last change i had two plugs that were blacker, and smelled like raw fuel than the rest. If the same cylinders have are at it again, I'll be moving the two injectors to the front of the car to see if it follows the injectors. I bought these used, and they might be not in the best condition.

 

[Great White Drake]

You want to see the first 2-4 threads with some color. See that line towards the bottom of the electrode? That's your timing mark. You usually want to see it right in the middle of the bend. Porcelain at the top is idle mixture, you need to cut it open but part throttle is middle and wot is at the base of the porcelain.

 

[Great White Drake]

Wallace Racing - Spark Plug Reading