Dryer not heating correctly

Dryer does not heat sufficiently. You can "Hear" it attempt to cycle but ignitor does not ignite. After a period of time when dryer cools, the ignitor lights the burner which runs for about 1 minute. Sometimes the dryer seems to work better, and also will light burner if you move the heat selector back and forth between fluff, low, high and auto>
Have done below repairs:

Cleaned air flow
Replaced solenoids
Replace hi limit thermastat

Will the cycle Thermastat part AP4056454 fix this problem?
Thanks Joe