Okay, so that rules out the valve and spark board as suspect because if either was bad, the broil would not work. So, that leaves the igniter and connector as suspect. The very small connector on the igniter can become loose, resulting in a poor connection. I would first pull the small spade connector from the igniter and use sand paper to clean the terminal on the igniter. Then, use a pair of pliers to gently tighten the connector and replace it to the igniter. If it still will not light, replace the igniter, pictured and available below.
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The link below is to the part you will need from a highly recommended company rated A+ with the Better Business Bureau. They offer a 100% money back guarantee, EVEN ON INSTALLED ELECTRICAL PARTS, for an entire year! They are the only company to allow returns on installed parts for a refund and offer a FULL ONE YEAR WARRANTY!
Igniter <----- CLICK HERE FOR THE CORRECT PART FOR YOUR MODEL
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