Buy a 10 cent gap measuring device & change it.
Because it's a V grooved iridium plug. To start with you don't want the V-groove plug as it's just another surface edge that detonation can occure at as fuel passes it.
After that, why would you buy iridium plugs? They cost many, many times higher than a copper plug, do not spark any better, and don't last years (read that as way appreciably longer) in an FI engine. You'll still be changing plugs every year, year and a half, so why waste the money? Copper is also an easy plug to read, and if you're real lucky, you'll melt a copper plug before you melt a piston, or a head gasket's fire ring under really high temps. Saving you lots of money.
You can buy the copper plugs for $1.50usd. The NGK 5691's (BCPR7EIX-11) are more $6.50-9.
But ya, whatever you wanna do it's your engine. The misfiring is probably the plugs eaten away & way too large a gap. But gap the plugs you buy down to what I told ya, and run the 7 heat range. Not the stock 6.
Linear Mode
