[m318x476070]

My dryer wouldn't heat and troubleshooting led me to the flame sensor. I replaced it, it worked for a while, then failed the sensor again. When the gas valve would open, i could hear a chattering or rattling. My initial impression was that it was the gas valve, so i replaced the coils. No change. Now i am beginning to wonder if the noise was the contacts of the flame sensor chattering? SO, my dilemma, what would cause this chattering, either in the valve or contacts and subsequently fail the sensor in rapid fashion?