running issues, runnin on 4 out of 8

[chimp koose]

I did a tune up many years ago in my teens and wondered why it ran so rough until I saw all the plug wires on the drivers side were left off . How many times have I had a no start only to see the rotor sitting on the fender ! To my credit I have never sucked a rag into a running motor .

[416Ford]

I have had a few run on 7 cylinders for a bit. Then I shut em off and put the number one plug back in.   :oops:

[Arnold]

It could be a blocked jet in the carb,years ago I had a 55 Olds that only ran on 4 but was getting spark on all 8 that after taking carb apart I found a blocked jet and then it ran on all 8.

 I had a nasty on off misfire on a mid 70's 3 cyl OMC..FINALLY found it..piece of casting flash had broken off in the float bowl..