Thought you'd like that coil. Don't forget to match it with some decent spark plugs. And widen the gap to take full advantage of your new juice. FWIW Bosch wires are actually pretty high quality (you notice MSD recommended spiral wires). Now, about cylinder #5 -- have you ever adjusted valves? (thank goodness for hydraulic lifters!) Tech manual is wonderfully vauge, but it does give feeler gauge measurements on page C:05:02. You'll need a 36mm socket to rotate the engine (muffler will have to come off for access). Is time consuming more than difficult. eMail me direct if you want me to walk you through it (brobertson@xxxx) Don't forget to buy new valve cover gaskets before you start! True carbon buildup doesn't burn off. It becomes part of the engine. Glows red hot, reduces cylinder volume, and otherwise causes mischief. Idea behind spaying water into engine is it will hit hot carbon deposits and crack them free. Unfortunately I've also heard of it cracking the pistons! You'll know your engine is hopelessly funked if it diesels after ignition turned off or clatters even with proper octane fuel (ignition timing can affect that one too). Otherwise, I wouldn't lose sleep. Lighter weight deposits will burn off (soot, oil, etc). Once you get fuel mixture staightened out combustion alone should do it (don't forget those new plugs). Can assist with carb or fuel injector cleaner poured into intake if desired. Not quite there yet, but you're on the way! Bill Robertson #5939