My kenmore dryer has started intermittently failing to heat. Most of the time it will go through a cycle without heating at all. Then every once in a while (about every 4th or 5th cycle maybe) it will heat normally and operate as expected.

I've replaced the thermal fuse and tested the heating element, the high-limit thermostat and the cycling thermostat for continuity. All test fine.

I suspect the next thing to check is the timer, right? Is there something else I should be checking? What would cause it to work sometimes, but not all the time?

Thanks for any help!
-micon