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

690 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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More than likely this is a valve guide seal or possibly the valve guide itself. When doing this make sure the piston is at the top for each cylinder. When you get the seal out see if the valve guide is loose in the head. Try to push the valve guide down into the head or try to rotate it. If it moves your screwed. Slide the valve down into the guide about 1/4" and see if it wiggles excessively in the guide. If there is too much clearance in the guide a seal may work for a little while depending on how bad it is.

Could be a cheep fix but possibly may need a valve job.
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