Wilson
As ever, lots of ways for an engine to end up with a misfire but I'd be suspicious of a combination of plugs and leads both being past their best. The connectors on the plug ends of the leads aren't exactly brilliant when new so throw a bit of deterioration of the leads and plugs into the mix and it could be the culprit. Don't know if you can use one of the Windows emulators on a Mac to get access to ProTune, I'm sure somebody must have tried
Calum
