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

693 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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Compare them to this chart:
Verrill: Plug Color Chart
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