I would check the plugs, especially if it started right after you changed them. Check and make sure all the plug wires are down good, and recheck your gaps. Look and make sure you don't just have a defective plug.
Took out the plugs to gap. They only had a few hundred miles. They were black like charcole. Would tht mean i have a bad plug ?
Doesn't black plugs indicate running rich (=increased gas consumption)?
Yeah . I still have the same plugs in the box where i took em out at. They are the same type plugs as i took out. Dont know how to tell heat range though.