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Discussion Starter #1
Anyone have any pictures of normal spark plugs? I'm using range 6's from NGK and the ground strap (arch that goes over the electrode) shows it is too cold...it shows the color start to change towards the end of the strap (closest to the electrode) but the porcelain has some black on it..kind of looks like this * or like a small black line..I was thinking that might be from the temeratures getting hot inside of the cylinder and making those marks, but I'm not sure and I see a few specks here and there on the porcelain, but not too much just a few...is this normal? I love this car and would hate to see anything bad happening to it..I don't hear any pinging...so I guess I'm good...hmmm...I did drive up a hill in 5th gear at a low speed with an A/C on to see if I hear pinging...dunno if that matters...like I said there isn't much of the specks or of the black burned marks on the plug and car still runs good! And the distributor is in the middle or so until I can get the car into timing mode and properly adjust timing..and it idles at about 2-3 small ticks above the white line under the 1000 rpm mark.

Thanks guys!!!
 

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Might be a little cold based on your description. If you do mostly around town driving, you will problably do better with the slightly hotter "5's."
 

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Discussion Starter #3
That's what I figured judging my the arch, but do you know what might be causing the black specks on the porcelain? Some times it can be a real small black line or in the shape of a really small asterick (*) I was thinking that might be caused by the temperatures inside the cylinders..can anyone confirm this? The small black marks are not all over the place..but I checked the porcelain on two plugs and there are about 2-3 marks that I noticed. Also, the arch on one of them appears cold...but on the other I could have swore that the color started changing below the other plug indicating it gets hotter than the other one..anyone have a clue why? The color doesn't start to change right where it is welded to the plug, but above that maybe about the middle if not lower or around there, so I should be ok as long as the color doesn't start to change close to the weld, right?

Thanks for your help!!

EDIT: The only reason I changed to 6's was to make sure I wasn't detonating, because I have not been able to get my car in timing mode to adjust timing, so I just set the distributor in the middle without the use of a timing light. I need to re-adjust my idle to..it sits slightly above the white mark under the 1000 rpm mark maybe 2-3 ticks above it.
 

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Discussion Starter #4
Looked at the spark plugs again...and all if not most of the black marks are gone..and this is with me driving in the same condition lol...so I don't know..I looked at the arches again though..and I think on 2 the color started changing close to the electrode, but on 2 others the color starts to change further down to indicate they are a bit hotter...any idea on why they are different? I figured all 4 should have been the same. On one of the plugs the color started to change right before the arch started to bend indicating it's a bit hotter, but not too hot. Too hot would be by the weld, right? Sorry to bug with all my posts, but I really appreciate all the input you guys give me back!!

Thanks!!!
 

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Everything you describe is normal for a car with some miles on it. The spots on the plugs are coming from combustion chamber deposits that occasionally free themselves. They tend to get fused to the porcelain. It is normal. Some of these spots can also come from additives in fuel.
Again, if you are doing a lot of around town driving, then the hotter plugs will most likely give you better gas mileage and stay a bit cleaner.
A good hard run every once in a while will clean things up. What we call an "Italian tuneup."
With unleaded fuels and the ECU wanting to run the engine as lean as possible, reading spark plugs is less reliable now than it was twenty years ago. Only big differences can now be noted (black and sooty as an example). The small differences you note really mean nothing. It is quite normal for the plug insulator to be bright white. Years ago we would have thought the plug was running too hot. But today it is just the result of cleaner fuels, and better engine management.
 

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Discussion Starter #6
Thanks for the help!! So, let me get this right...since my car has over 183,000 miles on it, it is going to run hotter than the same car with less miles, right? I was just worried, because like I said before I read that on the arch that goes over to the electrode..that if the color starts to change close to the weld..The car is running to hot and if the color changes close to where the electrode is under the arch it is running to cold. Right now about 2 plugs the color changes a little close to the electrode and on two it changes in about the middle or on one a little below the middle..and this was at around idle just as I pulled in to park. I just checked my old plugs and at about the same condition the color started to change closer to the weld that attaches the arch to the spark plug and since according to those plugs I was running a bit hotter and these plugs are a range colder I guess I'm fine considering on the old plugs I didn't hear any pinging or anything like that. Since the colors on these start to change further up than my old ones. No cracked porcelain insulator either. Need to change my fuel filter soon maybe that'll make it run a little cooler. I don't know when the previous owner has changed it.
 

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David99G20T said:
Thanks for the help!! So, let me get this right...since my car has over 183,000 miles on it, it is going to run hotter than the same car with less miles, right?
No this is not true. Your car may have deposits which may increase the chance of "pinging", but high mileage will not mean your car runs hotter or colder than normal.
If your car is running hotter than normal (temp gauge wise) this is more likely due to deposits in the radiator, timing not set correctly, air in the cooling system, or a bad thermostat. If you think your car is running hot because of the way the plugs look, but the coolant temperature is normal, then you do not have any problems. Forget about the plugs.

David99G20T said:
I was just worried, because like I said before I read that on the arch that goes over to the electrode..that if the color starts to change close to the weld..The car is running to hot and if the color changes close to where the electrode is under the arch it is running to cold. Right now about 2 plugs the color changes a little close to the electrode and on two it changes in about the middle or on one a little below the middle..and this was at around idle just as I pulled in to park. I just checked my old plugs and at about the same condition the color started to change closer to the weld that attaches the arch to the spark plug and since according to those plugs I was running a bit hotter and these plugs are a range colder I guess I'm fine considering on the old plugs I didn't hear any pinging or anything like that. Since the colors on these start to change further up than my old ones. No cracked porcelain insulator either.
I really think you are over analyzing the plugs. I can get your plugs to be any color I want depending on how I drive. Your plugs sound normal. A hotter or colder plug will have no influence on coolant temperature.
David99G20T said:
Need to change my fuel filter soon maybe that'll make it run a little cooler. I don't know when the previous owner has changed it.
Changing the fuel filter is a good idea, but will probably have no effect on temperature, especially if your engine is running normally.
 
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