Help me analyze my Spark plugs.

[jonnyg]

I decided to take a look at my plug(s) the other day, I think I'm due for new ones, especially with my engine mods (540hfm kit). This plug is from cyl. #1, I noticed the oil on the threads, which indicates replacement of the valve cover gasket correct?

What do the colors on the tips and prongs of the spark plug indicate? (lean or rich.....) Help me out here.

Thanks in advance.

[RagnarDanskjold]

Bump for a worthy cause.

Last time I checked, I also had that greenish tint on the insulator and I've been wondering what causes it. . .

[zot786]

From searching here, the oily threads means the complete valve cover gasket needs to be changed. I have a similar problem and will be doing so soon.

Make sure to use the NGK iridiums; everyones raving about them, and now, after trying I know why. I was using bosch platinum 4s, and were crap in comparison.

[r6jon]

In my humble opinion I think they look great - depends on how many miles they have been run though.

The green is probably copper oxide (copper vaporized from the electrode and then deposited on the insulator).

[habbie]

green specs = impurities in gas

[BMW///M3sdn]

Ive got a question, it looks like the prong closest to the camera, is firing onto the porcelain instead of the diode, does this make a difference? I recently changed my plugs, and almost all the prongs were firing onto the porcelain just like the close one on this picture.

[steve99m3]

How many miles are on the plug? IMO it looks good, even if slightly greenish. The green probably is from impurities in the gasoline and shouldn't be a cause for concern. Only if the plugs were white/ashen or black/dark would you have cause for concern.

[steve99m3]

Ive got a question, it looks like the prong closest to the camera, is firing onto the porcelain instead of the diode, does this make a difference? I recently changed my plugs, and almost all the prongs were firing onto the porcelain just like the close one on this picture.
Nothing to worry about if you're not misfiring at all.

[M3_boogie]

Sounds like you may have read this already, but if not, it is some good info for spark plug reading.

http://www.pelicanparts.com/bmw/techarticles/E36-Spark-Plugs/E36-Spark-Plugs.htm

[nightkrawler]

they look good imo also. i put the denso iridiums in my car a week or so ago. i cant say i really saw any large difference, cause the plugs i had in there were not worn out. but they are supposed to be a great plug and last much longer than even a platinum type plug. they are pricey, but if you love your car, i guess you want it to have the best of everything. my 2c

[shim]

they look good imo also. i put the denso iridiums in my car a week or so ago. i cant say i really saw any large difference, cause the plugs i had in there were not worn out. but they are supposed to be a great plug and last much longer than even a platinum type plug. they are pricey, but if you love your car, i guess you want it to have the best of everything. my 2c
i dont think anyone will "feel" a difference, even with butt dyno. iridium spark plugs are not supposed to have any gains. they are better than platinum spark plugs b/c the perform more consistenly. ask any turbo guy and you'll see why they like iridium plugs

[nightkrawler]

quite true, for the most part you aren't going to see any gain from new plugs unless your old ones are shot. still wanted to try them though, lol.

[AMPowerJ]

I noticed a much better cold start idle when I switched to Denso Iridiums FWIW.

[shim]

quite true, for the most part you aren't going to see any gain from new plugs unless your old ones are shot. still wanted to try them though, lol.
oh no doubt, i'm definitely gonna upgrade to iridium plugs sometime