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I know why my car was idling like crap...

691 Views 9 Replies 5 Participants Last post by  roncallo
Decided to take my own advice and put a set of NGK BP5ES in die Weisse Lady. Discovered two problems with the old plugs. The first was that they were Bosch WR9DC+ resistor plugs, and the wires were still Bosch resistor wires. Not sure how much difference that makes.

Here's the second problem:

Spark plug Auto part Automotive ignition part Automotive engine part Fastener

The numbers are the cylinder they came out of.

#8 isn't supposed to look like that, is it? Not only that, but what you can't see from the picture is that the gap is a lot narrower than on the rest. I didn't try using the gap tool on it, but it looks like it's half the width of the others.

The car runs and idles a lot more smoothly now. The big question is: where'd all that crap on #8 come from?
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From what I can see, the insulators on 1-7 all look normal. The electrodes on 2-7 look normal, too, though 1 looks a bit oily. I'm puzzled by the oil on the ends of the ground side, though, on all of them.

And then there's the crap all over #8. If it was a rich mixture, wouldn't it be affecting all 8 plugs? The obvious first guess is rings or some such, but the car has more than ample power, and is idling smoothly now with new plugs in it.
1) Valve guide seal

B) Oil control ring

III)Head gasket oil leak
Hm. The valve guide seal can be done without major disassembly, IIRC. I would think the oil control ring would take more doing than the head gasket, though...or am I not understanding what's involved in a head gasket replacement?

No way of knowing how long they've been in there, right? You know it's clean now, see how it does.
Yup. How long would you suggest I wait before pulling the plug to look at it? It's my fair weather daily driver, so it gets driven regularly.
Are they smog checked in your locale?
Nope. One advantage of living in Minnesota. Used to be that vehicles registered in the metro Twin Cities needed smog checks, but that requirement was eliminated a few years ago.
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