03-11-12, 07:05 PM
a very quick way to check for shorting is to fire it up in the dark. any arcing is easier to spot. the problem suggests that something was disturbed after changing the plugs. if the plug caps screw into the leads (do they still make them like that?) snip a bit off and screw them in again. i assume you havent mixed the leads up.. check the simplest things first.