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why slightly burnt spark plug at 65,000+ miles?

Discussion in '100-Series Cruisers' started by drexx, Jul 8, 2005.

  1. drexx

    drexx

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    09Jul2005 (UTC +8)

    My stock factory spark plugs, Denso SK20R11, has three of them slightly burnt at edge of the ceramic parts. It doesn't look as bad as this, only about 1/5 as bad, as this pic I saw on the 'Net (it's not mine!):
    [​IMG]

    Mine's a 2001 UZJ-100 with more than 65,000miles travelled. I wonder what caused this? Otherwise the spark plugs look very normal as defined in Denso's website. http://densoiridium.com/howtoreadusedplugs.php

    I'm currently invesigating this, then checking engine compression, checkin valve clearance, then putting the TRD Supercharger :D
     
  2. spressomon

    spressomon glutton Moderator

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    My OEM plugs, at 70K, had this discoloration...although not near as pronounced/dark...
     
  3. NMuzj100

    NMuzj100

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    Better explanation of the spark plug corona phenomenon

    Click Here - also from denso

    NGK on the Corona

    Nothing to worry about. Supercharge that beast.
     
    Last edited: Jul 9, 2005