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sparkplugs burnt quickly

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Old 04-05-10, 08:31 PM
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sparkplugs burnt quickly

i just put in brand new sparkplugs and 10.2mm wires less than 200 miles ago. i just recently took one out and it looked black allready. they looked pretty burnt for just 200 less miles. whats would cause this? i use 91 octane from shell gas stations. anything else just ask
Old 04-06-10, 12:48 AM
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black usually means rich mixture
Old 04-06-10, 02:02 AM
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please do tell us your car first and is it n/a or turbo ?
Old 04-06-10, 05:11 AM
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Yes, more info on your car and the specific spark plugs you are using. As said previously, if the center electrode insulator (ceramic part--red area in image) is black, your plugs are fouling with an over rich mixture of fuel-oil, or the spark is not adequate to effectively burn the air-fuel mixture. The color of the center insulator should be a nice tan or brown color. Black does not indicate "burnt" plugs, BTW.
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Old 04-06-10, 11:55 AM
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well its a 86 na sorry lol. and the middle diode isnt black just the outside around it. they are ngk(bought em according to whats the internet says trailing and leading) and maybe this has something to do with it but somehow one of my wires was a little loose on the plug and i push it back on. my car afr guage reads rich but i was told it was going to for a rotary and for the fact its a narrowband setup. its does read optimal at about 3k rpm in 3rd ( it bounces between lean and rich the whole optimal range) PS they are un gappable

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Old 04-06-10, 01:37 PM
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Stop using premium in an NA. It's pointless and may be what is fouling your plugs.

From all your other posts, it is clear your car is not running correctly. It is probably hideously rich, due to one of the things I have mentioned in your other threads.
Old 04-06-10, 05:46 PM
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well they havent fouled yet and the only problems with my car in a running stand point would be the tugging in my tranny in low rpm in first and second. other than that ervything seems to run fine. no white smoke since i got it running about a year ago. just figured they shouldnt be that dark already. Why not 91 i used it in my 87 maxima and it gots loads of power from it. is there such reason i shouldnt? figured it would help and as to the other threads it runs more lean now do to new fuel filter and i took one of those riduculous tornado things outa my intake. also used to have iat sensor chip but took out after reading FAQS. maybe it is the 91 maybe its not burning it all? maybe 87 would be better? and would i lose power because of the change?
Old 04-06-10, 06:14 PM
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Originally Posted by canonize-ryda
well they havent fouled yet and the only problems with my car in a running stand point would be the tugging in my tranny in low rpm in first and second. other than that ervything seems to run fine. no white smoke since i got it running about a year ago. just figured they shouldnt be that dark already. Why not 91 i used it in my 87 maxima and it gots loads of power from it. is there such reason i shouldnt? figured it would help and as to the other threads it runs more lean now do to new fuel filter and i took one of those riduculous tornado things outa my intake. also used to have iat sensor chip but took out after reading FAQS. maybe it is the 91 maybe its not burning it all? maybe 87 would be better? and would i lose power because of the change?
you dont get extra power from higher octane, you run higher octane to stave off detonation on turboed/high compression engines.
Old 04-06-10, 06:26 PM
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so simply you guys are saying that its the 91 leaving carbon on my plugs. i should simply switch to 87?
Old 04-08-10, 01:26 PM
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Your Maxima doesn't get loads of power from running a high octane fuel unless it was tuned to take advantage of that fuel and was retarding timing/adding fuel at lower octane to avoid detonation. Or it was in such terrible shape with such immense carbon buildup that it couldn't run the lower octane stuff without detonating.

Yes, without question, try running 87 octane in your NA. You will save money, make more power and get better mileage.
Old 04-08-10, 07:44 PM
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thank you cause my gas milage is like 5-10 it seems. i put 2 gallons in and ran like maybe 10-15 miles tops and almost used all of it
Old 04-08-10, 10:45 PM
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you have something wrong if you are getting 5-10mg... you should only be running NGK brand spark plugs, BUR7EQ for the leading and BUR9EQ for the trailing. are you experiencing any problems with the way the engine performs?
Old 04-08-10, 11:22 PM
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engine performs nicely . will walk a pontiac g6. and i do think those are the plugs i have. i have been thinking now that my intake being made by myself is like most others but ive heard that i may want to use the stock air box to keep the filter from sucking all kinds of debris and from useing the hot engine air. maybe this is my problem its only been maybe 500 miles since i did my intake but maybe since im in a dusty area it getting clogging all ready. if you can look at my profile pic and see my intakemaybe tell me what you think? its got a tubing off the front of the intake to a inake horn in the front bumper for added air flow.
Old 04-09-10, 07:23 AM
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Is that the "bottom" of your air flow meter I'm seeing just upstream of the filter? If so, you need to rotate it so that the flat black portion is more or less parallel with the ground like it was in the original orientation.
Old 04-09-10, 09:40 AM
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The AFM pointing down will certainly cause the car to run way too rich. Way back in the day when my car was NA and I still had the stock ECU, I had the AFM positioned pointing down. The result was enough fuel to make the cat glow red and max out the emissions dyno for unburned hydrocarbons. Without question, level out that AFM.
Old 04-09-10, 06:44 PM
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ok made the switch and already can feel a difference and see better milage(on a small scale) but to what you guys are saying i need to level it off in stead of pointing it down i can do that probaly... and as far as the setup goes its ok? ill take new pics sometime. been painting and working on it alot getting new interior parts new guages. well thanks for info didnt no that it mattered the way it was pointing but now i no.
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