If the lobes have marks,it's not a good sign. The lobes should be smooth and shiney. If the plug leads are original ,plus the cap and rotor, it's high time they were changed. Don't try shorting a plug because the ignition produces 20,000 Volts and it will hurt! plus you can damage the EZL module ($$$$) . thats why that yellow sticker is on the aircleaner.