^^^^^^
There is your problem there
I have not known anyone who did not have a problem with it since when it
first came out.

First of all, plug wires can look fine and still be bad.

If it has a distributor, I would first change the distributor cap and rotor.
If it has different spark coils for the cylinders I would check them as
follows:  First, locate the coils in the light.  Then, with the engine at
normal operating temperature in a dark location (the darker the better),
look at the coils and see if you see any sparking or arcing at or near the
coils.  If so, replace both (all) coils even if only one is suspect because
if one is bad the other(s) isn't (aren't) far behind.