Boxster 3.2 S engine problem! Misfiring?

[911monty]

Change the spark plug on that bad cylinder. It is probable the plug has carbon tracks due to the previous bad coil pack, this will cause the plug to misfire along those carbon tracks. Under hard acceleration the air fuel mix is more dense and harder to ignite, which requires more voltage to jump the plug gap. This increased voltage then travels the carbon tracks. Give this a try.

PS After a few hours rest (from New Years celebrations) I should have said the increased resistance from Fuel /air in the cylinder causes the spark to travel the lower resistance carbon tracking from the previous misfiring.

[BoxsterSteve]

Given the amount of oil gunk there, I'd change the plug tubes and o-rings as well. May have nothing to do with your misfire, but it can't hurt either.