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hey guys my car studders at low rpm before boost, checked my spark plugs and the top of the electrodes looks like sandpaper gritt. I do extensive idling when on the way to work with a stock rb20det except for intake/exhaust. Half of the plug is brown/half white-ish colored. I heard a rumble when revving it, could be cas bearing, but it sort of went away. getting new sparkies soon , but they def. did not look like this before, looks unhealthy. leaking out?

my camera sucks so be patient , just look at the half and half pictures to get an idea.

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its a strong running motor, i just changed spark plugs , and now it breaks up at all rpms slightly, i used delco double platinum since thats the only ones i could find today, cross referenced with pfr5a-11 .... i am using the silvia non turbo stock fuel pump with 120 km on it..... maybe it is on its way out? the plugs look overheated

  • 8 months later...

Plugs look fine to me.

Here in Adelaide we don't see extended idling so my plugs have always come out clean as a whistle.

If you want to take a better pic place the sparkys on a table and then use the macro function of your camera.

I've found 6's up to around 240rwkwish to be ok; over that they show as running too hot.

I've since changed to 7's and the plugs have a much nicer tan colour instead of the porcelin coming out near shiny looking white after a few hard runs on the dyno.

  • 2 weeks later...

yep th plugs are fine. i just changed my plugs last weekend and they were similar color to yours. its just running rich, normal.

gotta be careful if the plugs are white... means its going towards a stoich/lean mixture..... stoich is good but means hotter temps which is why the plugs would be white

i use #7 plugs on mine.. people say i should use 6 but 7 is fine.

  • 12 years later...

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