On a standard dual coil build, do you ever feel like one of your coils is heating up faster than the other?  You should probably check to make sure both coils are firing up at the same time, otherwise you may create a short in the circuit.  Here’s an easy way to fix the problem:

Check to see that all screws are tightened up.  Sometimes the screws can come loose by regular use.  If they’re still firing unevenly, you can try squeezing the coils together with ceramic tweezers.  The goal is to get both coils firing together again.