Originally posted by Mattback
too cold of a plug won't cause pre ignition or detonation, it will simply foul out when the car is cruising, because there won't be enough combustion heat to keep the plug at self cleaning temperature.
timing and carbon build up will probably both do it on a ka
oh boy, I did write that... thanks for covering me.
Anyways, clean the engine to eliminate hot spots (don't really think it'd be that bad but it's an idea).
Go over the fuel items and IACV suggestions first.