Well, I've noticed that when I'm driving, my tach needle jumps up every couple seconds. It only started doing this when I unhooked my MSD 6a box. The box was sucking power, so my car wouldnt start. I did pull a spark plug to do a test, and i think that is what might be acting up. I havent had the time to check it. Any ideas?
It's a stock 5.0.
put the MSD box back on and use a battery disconnect switch when parking?