Rich tune affecting the spark plugs?
Rich tune affecting the spark plugs?
Since the stock tune is so rich, how is that going to impact my spark plugs? I'm not a fan of messing with the plugs just to mess with them, but if they look anything like my exhaust, they have to be carbon caked...
Mine are always getting fouled up from my Rich tune I need to re tune it sometime soon lol But yes rich tunes will affect your plugs mine don't last for but a few months then they get fouled up from the rich tune... But hay plugs are only $10 for the 4 so its not to big of an issue and it takes 10 min to do... You probably should replace then anyhow like Every oil or every other Oil change.. I have always done it every other or every 3 months Just so they are fresh and I try to just do other things like diff and trans check every oil change to see how they are doing... just part of maintenance work you should always do for your Evo 
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Sorry, couldn't resist myself after that suspension thread. 
You may know suspension better than me, but you're in my section now, homeslice. J/K Anyway... to answer your question, the overly rich condition is going to foul out spark plugs way earlier than what the maintenance schedule calls for because of accumulation of fuel residue and carbon build up. This can result in misfires or in bad cases, total loss of spark in one or more cylinders. If you take your plugs out and they are black, you are running rich. If they are grey and have light brown specs on them, you are running lean. Not that it's an issue on the stock tune, but running too lean, if you were wondering, can cause the spark plug tips to burn/melt/fall off inside the combusiton chamber and when that happens, bad things happen.
In any case, if it were me, I'd be more woried about the fuel dilution that's occuring in your oil supply from the overly rich A/F ratios than I would about the spark plugs. Fouled out spark plugs from running too rich can't cause catastrophic engine failure, but oil that has too much fuel in it most certainly can. Go check out my thread called "fuel dilution in oil problem" for more info. Hope this answered you questions.
Last edited by STi2EvoX; Jan 4, 2009 at 12:08 AM. Reason: fixed typos
We have had a couple 10's through the shop with fouled plugs from the factory tune.
The 10 plugs are not $10. They are not the "cheaper" coppers like we can use in the 8.
They are NGK - ILKR8E6 and are around $14/each.
They are NGK - ILKR8E6 and are around $14/each.
If you feel the need to ask this question, then perhaps you need to do some research on the basics. Sorry, couldn't resist myself after that suspension thread. You may know suspension better than me, but you're in my section now, homeslice. J/K Anyway... to answer your question, the overly rich condition is going to foul out spark plugs way earlier than what the maintenance schedule calls for because of accumulation of fuel residue and carbon build up.
This can result in misfires or in bad cases, total loss of spark in one or more cylinders. If you take your plugs out and they are black, you are running rich. If they are grey and have light brown specs on them, you are running lean. Not that it's an issue on the stock tune, but running too lean, if you were wondering, can cause the spark plug tips to burn/melt/fall off inside the combusiton chamber and when that happens, bad things happen.
In any case, if it were me, I'd be more woried about the fuel dilution that's occuring in your oil supply from the overly rich A/F ratios than I would about the spark plugs. Fouled out spark plugs from running too rich can't cause catastrophic engine failure, but oil that has too much fuel in it most certainly can. Go check out my thread called "fuel dilution in oil problem" for more info. Hope this answered you questions.
Sorry, couldn't resist myself after that suspension thread. You may know suspension better than me, but you're in my section now, homeslice. J/K Anyway... to answer your question, the overly rich condition is going to foul out spark plugs way earlier than what the maintenance schedule calls for because of accumulation of fuel residue and carbon build up. This can result in misfires or in bad cases, total loss of spark in one or more cylinders. If you take your plugs out and they are black, you are running rich. If they are grey and have light brown specs on them, you are running lean. Not that it's an issue on the stock tune, but running too lean, if you were wondering, can cause the spark plug tips to burn/melt/fall off inside the combusiton chamber and when that happens, bad things happen.
In any case, if it were me, I'd be more woried about the fuel dilution that's occuring in your oil supply from the overly rich A/F ratios than I would about the spark plugs. Fouled out spark plugs from running too rich can't cause catastrophic engine failure, but oil that has too much fuel in it most certainly can. Go check out my thread called "fuel dilution in oil problem" for more info. Hope this answered you questions.
I deserve it... and I did the research, that's why I asked the question. As I posted (last month!) I don't like to mess with spark plugs just to play with them.And I know about the oil dilution (I responded in that thread too because my oil stinks).
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Ours come with unobtanium plugs .. replacement factory plug is ~$25-30 ea !!
The only difference recently is that Evo 9 and X both have little to zero aftermarket support. The X plugs are only sold at the dealer.
I take it, that if i take one out and it is fouled i should take it to the dealer and have them replace under warranty correct! Or just wirebrush clean them?
Last edited by Papi4baby; Jan 5, 2009 at 10:24 AM.
Thanks!Im not sure what dealer is crazy enough to try to sell plugs for the price quoted earlier in this post. $25-$30???
