This one stumped me a bit. The dryer would work sometimes then not. This came down to the igniter working intermittently. We checked each component by itself using an ohm meter but everything checked out ok. So we ended up checking with volt meter with dryer on (attempting to start ) We were checking for 120 at each component. When we got to the primary coil it was only getting 54 volts. So we unplugged the wires going to the flame sensor and jumped them out which gave us 120 volts at the primary coil. So I guess the flame sensor had too high of resistance after it sensed the igniter then wouldn’t work till it cooled back down maybe 10 minutes later. We tested this by keeping the jumper connected to the flame sensor by wires and starting the dryer. The igniter would turn red every time, but no flame. So, to get the coils to power we had to increase resistance in the jumpers just like the flame sensor would. We did this by removing the jumper on one side ( be careful it has 120 volts cruising through it ) and the burning ignited.
We ordered a new flame sensor and all works great.