Concerning my 300ZX ITS that had clean plugs on 2 - 4 - 6 and fouled plugs on 1 - 3 - 5...
I looked at a ton of stuff to see what I could see and for some reason decided to open up the distributor to look at it. I found that the etched mylar piece no longer had a flat side on the center, it was totally round; the keyed piece that holds the mylar piece in place was also round in the middle; in fact everything inside the distributor was wallowed out and no longer keyed.
I don't have a clue how it happened.
Put "new" (it has at least 100k miles on it) guts in the distributor from a spare parts car -- including a "new" trigger; new spark plugs to replace the fouled out ones, and it runs great. I let it run until the thermostat opened and then for another 20 minutes after that. Ran it up to 5k rpm many times and no miss at all. In fact my sweet wife said she hadn't heard it run that good in a year or more. It idled smooth and I could not detect a single miss throughout the rpm range. I also pulled a spare ECU off the parts car and threw it in the race-spares box just in case.
I hope this solves the problem. I will run it at the local 1/8 mile drag strip as soon as it opens in February just to make sure.
Thanks for all your advice,
Bob
