[Hil911]

I took out plug 2 and cleaned it. Crappy, but I've seen worse. Resistance was about 4.5 KOhm which surprised me. So I took out number 1 and it was the same.

Cleaned plug one as well and put them back swapped over.

They now both show a reasonably regular firing pattern. There seems to be the very occasional missed beat at idle.

So - a timing gun shows you whether it should be sparking. Missed pulses can come from anywhere in the distributor cap through plug system. A pulse shows that electricity flowed right through the lead where tested.