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What used spark plugs look like....

Posted: Wed Aug 08, 2012 8:54 pm
by The X
Thought I'd share....
I replaced my spark plugs at 45,000km a couple of weeks ago...
I know it's not needed as the Iridiums have a service life of around 100,000k - but I got them at a 20% off sale ages ago at a cost of around $8 a pop, so no biggie.

The brown ring on the ceramic insulator is "normal" to an extent, tho i'm not sure it should be that much on 45,000kms :shock:

You can see the firing electrode tip end looks fairly clean, a small amount of deposit on it. The needle tip looked fine also the flat bit had some deposit but a groove indicating that any spark would have "contact" between the needle point and the metal conductor.

You can see some of the deposits falling off from the 2nd spark plug in the last two photos... :)

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Posted: Wed Aug 08, 2012 8:58 pm
by LZY_EYE
Mine were almost identical when they came out too...

Posted: Wed Aug 08, 2012 9:06 pm
by Mitch
Does servicing swap them out on the 45000 service as my car as already had it but unsure if they actually changed them as the car is at 48550 now . Thankyou

Posted: Wed Aug 08, 2012 9:08 pm
by LZY_EYE
Nope, they stay in till about 80-90,000kms if following service book.

Posted: Wed Aug 08, 2012 9:09 pm
by The X
No Mitch, I think they do them at 90,000 as the spark plugs from factory are the same NGK Iridiums i replaced them with and they have a service life of 100,000k.
I guess closer to the 100,000k mark they carbon build up is more and inhibiting the quality of the spark.
Being they are such a low cost item, i swapped them out myself at 45,000. A nice clean quality spark can't hurt. :)

Posted: Wed Aug 08, 2012 9:11 pm
by Mitch
Ok Thankyou so much Pete. Have a good night :-)

Posted: Wed Aug 08, 2012 9:15 pm
by cj_sx_2011
it wont hurt warrenty if we done them at 45000 would it? i think 90 is way to long to change spark plugs.

Posted: Wed Aug 08, 2012 9:17 pm
by The X
As long as you use the correct spark plug with the same heat rating and gap distance, no warranty issues. Nothing wrong with going above and beyond the scheduled service requirements.

Posted: Wed Aug 08, 2012 9:27 pm
by DORA_ANNE
Pete Mitsubishi changed mine around my 90.000 service & they said that's about the normal K's they change them ....

Posted: Wed Aug 08, 2012 9:27 pm
by cj_sx_2011
thats what i was thinking aye. its not like spark plugs are dear. lol. but seriously 90tho is along time, whats the normal time of doing plugs in our car?

Posted: Wed Aug 08, 2012 9:41 pm
by The X
Normal time as we've said a few times is 90,000km. I don't know the "length of time" interval it has to be done, you'd have to check the book, perhaps at the 4yr mark they might tell to swap them out. dunno.

Posted: Wed Aug 08, 2012 10:36 pm
by cj_sx_2011
i didnt know i sweared soz pete, yeah i dont think ill wait that long to be honest.

Posted: Wed Aug 08, 2012 11:57 pm
by squala
Ninety thousand kilometres is when Mitsu tells us to change the spark plugs, but the real question is when we should actually replace them. I want the spark to be uncompromised at all times.

Posted: Fri Aug 17, 2012 1:02 pm
by empror
Wish I had taken photos of mine when I changed them at 80,000..
Yours look clean and almost new compared to how mine came out...