I bought a set of 8mm taylor spark plugs long ago,

and 1 of the wire somehow got intact with the exhaust manifold
and burned off..
I had a spare 7mm wire in my trunk so I used that to
replace the burned one.

so I have like 5 8mms and one 7mm running..
is this bad? if so what can this cause?

or is it something I shouldnt worry about?
I mean, so far I noticed no different but I have all these small problems
that I cant really identify and just would like to know
what this can possibly cause.

thankyou!

 

Normally, the difference should not cause any problems. I'm almost hesitant to comment, but size doesn't matter....