I've always wanted a gtp I found one drove fine then it started to have a mis fire in number five changed plugs wires no luck hooked up a noid light and nothing on 5 hooked up a pcm from a s/c Buick riv and the noid lit up but the car wouldn't run bought a new pcm and had it flashed and its still doing the same thing car runs but there's no pulse to number 5. Any ideas please help I got close to a grand in to this thing I've owned it 3 weeks and got to drive it once