This problem has been perplexing me for a few weeks
I've got a 98 S-10 4.3L X code engine with 107,000 miles on it. I recently gave it a tune-up including new AC Delco Platnum plugs gapped to .060 in, Bosch plug Wires, Bosch cap and rotor, and new ignition coil. I also replaced the fuel filter, air filter, and the pcv valve. After all of this was done I noticed the truck was missing a little at idle speed. Upon further inspection I noticed at night that I could see arcing from the sparkplug boot. I have rechecked all of the gaps and they seem to be okay. Even the coil arcs a small bit when the throttle is opened. I used a small amount of dielectric grease on the boot at the spark plug end and anti-seize on the plug threads. I have read a lot of cautionary comments about using anything other than AC Delco components so to be thorough I bought the Delco cap and rotor, plug wires, and ignition coil to try and eliminate the arcing but no luck, it still arcs. Acrs at the coil when the throttle is initially opened and at the sparkplug boot at idle speed
. Through all of this the only code being thown has been P0300 Multiple/Random Cyclinder misfire. I will take any advice I can get at this point
. I have a multimeter so I can make basic voltage checks and resistance checks. Is it possilbe that the Ignition Control Module (IC on the bracket next to the coil) is bad? What is the function of that modeul anyway? Or have I missed somehting really simple?