unscrew the spark plug cap from the ht lead,put your finger on the end of the lead and pull the cord,(as if you were starting it).
If you get a jolt then you know the coil is working,and it propably needs a new plug,
no jolt, then you need a new coil pack,
I know this method is a little unorthodox in its approach but its one way of checking.
crazy george
March 2012