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Ok, Plug Readers… Here Is A Fun One.

Kile Brekke

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What do you think? Too Rich? ;)  Ha. 


This is #1cylinder. I probably let this go for about 5000 miles before changing the plugs. 

Car was running "fine" too. Maybe a little poor on gas mileage. 

This is fairly consistent. Every plug change for the last couple years I get this build up. 


I need to get this sorted. My car burns some oil, of course. Probably a quart every 1000 miles.
The first cylinder is definitely the worst. The other 3 have build up, but you can at least see a visible gap! 


The car isn't drinking water either. So I don't believe it to be head gasket related unless you guys have a theory on oil passing through internal head-gasket passages? Can that happen?

Probably bad rings, definitely worn guides as I get some blow by on a de-acceleration on the freeway.


I'll have to do a compression test as well.


In the meantime, more frequent plug changes are in order. 






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I recently did a plug wire change—same build up after that.

Could/would water do this?

How much would it even take to make that happen? Like I said, i'm not losing any water (that I can easily measure, anyway).

Anyway, It's probably pointless to speculate without doing the leakdown test.

But what is weird/impressive to me is that my car runs 'fine'. And by 'fine' I mean, it starts up every morning, idles well, and takes me 100 miles a day round trip on the freeway and keeps up with the flow. And then does it again the next morning.

Not that it will last too much longer, of course, in this condition.

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I recently did a plug wire change—same build up after that.Could/would water do this?How much would it even take to make that happen?

No, water would actually steam clean your chamber and make it all pretty and shiny (not that water is good though)

Have a look at the pipe that comes from your valve cover into your manifold if there is lots of oil in there.

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I have been running NGK BP6ES for over a year now.

I attached an old photo. This photo is over a year old with some Bosch plugs.

I've had a shop take a look. They basically said I have bad rings, bad valves/guides etc.

It needs some head work essentially.

I don't know where my timing is set at. But I did have a new coil and pertronix installed last summer.

Timing would've been set back then. It didn't change the build up on the plugs though.

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The bosch 8 is a hotter plug than the ngk 6 the ngk equivalent heat range would be an ngk 5. The bosch looks hot and lean, but the ngk doesnt look like it is the correct heat range either.

You can do a compression test, leak down, run a vacuum gauge et al, as suggested. But in the end as your mechanic has suggested, your engine might stand a full rebuild.

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The build up on the plug is from the ash content in the oil which is usually white color, running rich result is black carbon deposits on the plugs. Study  low ash oil for diesel engines for the next oil change with new plugs. It would be interesting to see  the ash amount if you did that .

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