Slant Six Problem =( ???

swissracer28 said
my slant six just all of the sudden started running weird and will not go over 15mph but if i unplug number five cylinder and it runs like a champ i have made sure the timing was correct and also checked out the carburetor any ideas??

Is the interior of the cap damp? Does it have carbon tracking present?

Also try swapping the plug to other positions and then, independently, the wire. Does the problem/fix follow the plug and/or wire?