Changed Plugs And Grey Smoke

[tdkmatt]

hey i changed my plugs today to iridium plugs today and for the first couple of hard revs alot of grey smoke came out of my exsaust, and it smelt like metalic, any ideas? and my gs said when i drive off in the morning and it happens sometimes, befour the plug change

[GTS-t VSPEC]

Grey smoke is better than white or blue smoke. It just sounds like unburnt fuel to me, which is fairly normal on Skylines. It could be that the gap on the plugs aren't producing a clean burn when they're cold, so you could try playing with gap sizes. But I don't believe it is much to worry about.

[tdkmatt]

my mechanic said to gap it from 1.1mm to 0.7mm but the 1.1 is designed for the rb25det

[br3ndan]

i have mine gaped at 0.8. which is the common gaping for mildly modded r33 gts t's.

[inthisglass]

i dont see what the fuss is all about

copper plugs work just as well plus they are cheaper

gap them to 0.8 and see if that works

if not then you may have a different problem

[tdkmatt]

yeah, on the package it said not to regap because of the tip of the plug can get damaged,

[tdkmatt]

would the gap being to big make it missfire? when it hits boost and a plant my foot it makes like a popping sound and sometimes you can hear and feel it missfire, i allways back off when that happens but could this be the cause?

[GTS-t VSPEC]

Yes, plug gap and the amount of boost being run can often lead to misfire. The fact that expensive platinum plugs don't like being gapped is one reason I never use them, I prefer the coppers, as there cheap and can be gapped to suit the need. I've run coppers with 600rwhp, so there is no issue with them. A new set everytime I service it is a cheap investment.

[michael87]

Missfire could be your coil packs if you have already gapped your plugs.

I bought myself some splitfire coilpacks and irridium plugs gapped at 0.8 solved all my problems.

[Ehgriez]

JJR coilpacks and coppers solved my misfire, dunno about grey smoke though..

[br3ndan]

u can buy pre gaped irridums @ 0.8. Which is what you should have done....

[R DIRTY 3]

I had Iridiums but they actaully caused problems...took them out, went to copper and problems have never come back.