When removing plug wires, be gentle and only pull them from the
boot over the spark plug. Do not yank the middle portion of the wire, as
the electrical conductor has carbon-impregnated filaments for radio
suppression that can be damaged. Be sure to record which wire goes to
which cylinder. If in doubt, tag or label each wire.
Arrange the plugs in order in order to compare readings. In this
instance, four of the plugs read differently, indicating a carburetion
problem.