Usualy the secondaries fail under high temp. So if you have been sitting in traffic usualy thats when they will fail(they just dont open) Try taking the little plastic cover off. And if they still fail to open. Take the box of and mount it on the backside of the heatshield on your intake. I had the same prob. and i have the same intake and when i moved the imrc box over to the intake and off the valve cover it hasnt failed since.
and regards to your sparkplug ? Everyone uses the stock double plat's. If you do a search im sure you can find a part #

98 csvt t-red.. sho-shop intake, b&m, fidanza, spec1 clutch, Torsen, DMD,optimized Y& TB, Brullen, rear strut bar,h&r's,17" konig traffik's. "I say what I mean and I do what i say"