How much power do you have their and how did you measure it? The igniters have a massive voltage to create a spark.
If their really is sufficient voltage there then the problem is more likely to be on the earth.
Make sure you have a good earth at both the igniter and the piezo generator. Their is really not much to go wrong other than that. I am a but confused still as to how you measured the voltage though. Most meters even if they are capable of measuring such a high voltage (thousands of volts) would take far longer to display the reading than the voltage is actually present for. You could try touching the igniter while you operate it like I did once but I wouldn't do it again. I have never had a shock like it. Some kids experiment with drugs, I tried piezo igniters. I promise you the igniter is far less addictive!
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