Spark Plug Condition?

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Looks normal to me, and the 6th plug seems to be within normal range of variation compare to the other 5. It is not lean, plugs in modern engine all looks sort of like that nowadays and drives fine.

Check other places for rough idle, like dirty sensor, dirty idle air control valve, vacuum leak, disconnected sensor / broken wiring (mouse / rat chew), etc.
 
It is almost impossible to determine which way we should index plugs. I know everyone says to point them a certain way, but gas flow is hard to predict.
And plugs with modern alcohol fuel are tough to read.
You read the base of the porcelain after a high speed, full throttle run, and 'cut clean' No regular driving or idling.
 
Since we have a champion engine builder in the family we index most of our plugs. Generally speaking you point the electrode at the intake valve(s). It can make a real difference at higher engine speeds but is unlikely to do much as most modern ignitions are quite stout these days.

And there is no magic perfect number for A/F ratio, it varies by setup.
 
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