Well the first thing you would notice is missfiring ,you may also hear a high pitch cracking noise as the spark jumps to earth out of the side of the lead somewhere,the best way to check is to run the engine in the dark and just look at the leads to see if you can see any blue sparks going on.darker the better and if it is arking out you will see it believe me.
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Well the first thing you would notice is missfiring ,you may also hear a high pitch cracking noise as the spark jumps to earth out of the side of the lead somewhere,the best way to check is to run the engine in the dark and just look at the leads to see if you can see any blue sparks going on.darker the better and if it is arking out you will see it believe me.