help reading out spark plug condition

upontheriversky

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hi,

i recently serviced my car and asked the mech to take out the spark plug to see the condition of it,

below is the pic:
2012-02-10113551.jpg


it looks like its in healthy condition judging by the light gray deposit but the cracks look like i have been experiencing detonation

any help?
 
hmm..does not look very healthy..
a healthy one should be brownish at the ceramic and the electrode,which suggest good AFR condition.

btw, when was the last plug change ?
 
some will use sandpaper & sand off the burnt part & use it again...
 
hmm..does not look very healthy..
a healthy one should be brownish at the ceramic and the electrode,which suggest good AFR condition.

btw, when was the last plug change ?

the plug has been in for 15k, its an iridium

i would say the plug is burning too hot......

you need a colder plug.........

any sifu wanna comment ?

thx for that. ive been thinking of using colder plug too


i have 2mm oversized piston fitted in, exhaust mod, oem airbox and filter and CAI. is the mod enough to cause lean af?

is leaning of af is what causes the plug to burn too hot?
 
hi,

i recently serviced my car and asked the mech to take out the spark plug to see the condition of it,

below is the pic:
2012-02-10113551.jpg


it looks like its in healthy condition judging by the light gray deposit but the cracks look like i have been experiencing detonation

any help?

I would need a very close up picture of the plug in order to tell. use a digital camera in macro mode and take the picture of the centre electrode and porcelain. Like this picture here and the same angle as well.

images


From the picture I can't see any cracks. If there are cracks in the porcelain its definitely running too hot. What car is it in and what plug code is that. From the picture it looks like the car is running abit lean. Can you hear actual detonation on the car? Looking at this plug I would go one step colder and see how it goes. If it looks ok then I would stop there if not I would even try 2 steps colder depending on the look of the plug, driving style, type of car/engine and mods.
 
The plugs show that your engine are running lean ...

I been experience with Plug Condition Vs AFR for countless of time .... this is just fairly lean and should not causing any detonation but will certainly do harm to the combustion chamber/piston dome .... if you have a AFPR,adjust to increase the fuel pressure and try it out ~
 
Too lean (diy) , not enough burning...you need richer AF mixture. FC would be good but power might optimum
 
I want to borrow thread. If I drive my car hard like uphill Genting. After that I notice that my exhaust smell like burning smell. Any related to this?
 
Too many variables to make a judgement on plug.
From the color it looks like you have a lean condition but if engine was at extreme load you should have heard some pinging.
Fuel additives nowdays will give a grayish color to the plugs also, should have same co;or at least three threads up, try to get a better angle on picture.
But if you have cracks on porcelain it is too lean.
 
I want to borrow thread. If I drive my car hard like uphill Genting. After that I notice that my exhaust smell like burning smell. Any related to this?

Could be your brakes, if manual maybe your clutch too....

---------- Post added at 03:01 PM ---------- 6 hour anti-bump limit - Previous post was at 03:00 PM ----------

hi,

i recently serviced my car and asked the mech to take out the spark plug to see the condition of it,

below is the pic:
2012-02-10113551.jpg


it looks like its in healthy condition judging by the light gray deposit but the cracks look like i have been experiencing detonation

any help?

Looks like running lean. If overheat will turn yellow.....
 
well for me it seems to be a little bit fine but if you are not feeling it right than you should probably change it what so ever i mean i would have been changed them if the plugs were lean i mean you could see exactly in the picture right and if there are cracks in the porcelain then why take risk simply just just them if you would like to........
 
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