My 1996 Plymouth 2.4L has the same distributor-less coil-pack system, termed "wasted-spark" since 2 cyl share a coil. The factory spec was 60 mil spark gap, but after 100K miles it started misfiring bad when going high-throttle at low speed, like on an on-ramp. Could be the PCM was damaged slightly after a front-end side hit which knocked it loose (ignition circuit is in PCM). I lowered the gap to 50 mil, based on a TSB for the same engine w/ turbo-charger, and no more misfires. A turbo boosts the cylinder pressure even higher, making sparking harder.
