I have a chevy truck that has a problem w/the wires arcing at the boots that surround the plugs. It doesn't do it when the engine is cold. But after it warms up about 10 minutes it starts idling rough and at night I can see the arcing. It is usually 2-3 plugs on both sides, sometimes all of them. I have replaced the wires and replaced the plugs twice, using AC delco plugs. It has the 350. I have also replaced the d-cap and rotor cap. I have sprayed the arcing w/WD-40 which eliminates the spark for 20 secs or so before it comes right back. I have tried sealing the end of the boot around the plugs with dielectric silicone grease which gets hot and retreats w/the help of gravity.
Any ideas?
MS