Yea sounds like loose wire or bad connection...or a connection touching somewhere it shouldn't lol
http://www.grandprixforums.net/my-06-gp-gxp-72403.html OBX headers, TEP tranny cooler, ls1 IM fuel rails and injectors, ls2 TB, ls7 MAF, full custom exhaust, Quad retro headlights, full out front and rear suspension work, tuned by HPT by me 8====>