Don't know if this has ever happened to anyone, hoping for some insight other than overtightened.

My spark plug , only the 2 cylinder from the bumper, keeps getting hairline fractures in the porcelain section of the plug. I've gone through like 3 plugs in like 4/5 months. Any idea's?

The effect BTW was misfires under WOT, and if the crack was bad then under partial throttle it would misfire.

 

what plugs are you using? i've never had a problem with f6dtc's, and ngk's are good if you want a cheaper plug

 

what kind of plugs are you using?

 

Probably cheep plugs, or a combination of overtighting and cheep plugs. Possibly the wrong plugs too, what kid are you using, that would help.

 

Wrong heat range maybe?

 

NGK BKR6E gapped to .28

Been having some misfiring under wot problems too, im replacing my fuel filter tomorrow. If that doesnt fix it maybe I'll try bkr7e.

 

you shouldn't really need bkr7e's but it might help, i would go with f6dtc's