bootybay said:
Only had one go bad on me and it was the cable where it enters the coil, so it wasn't realy the coil but not a lot you can do, ok if it was the connector end.
Symptoms, mainly very erratic with nothing you can do to clear it, especially once you start to move the coil, mine was falsing at the end of each swing to start with and i thought it was my swing style that was causing it. A friend has a hairline crack in one and it worked ok unless it was wet, then it went haywire.
Only sure way to check is try another or put yours on another machine and see how it goes