I have low or no heat on my 4 year old gas dryer, so I tore it apart and got to where I could see what was happening.

I start the cycle and the ignitor turns on. Then the gas valve opens. Then the burner ignites. Usually the burner will run for 3-5 seconds and then burner shuts off. Within a minute the sequence starts again with the 3 to 5 second of the burner burning. Then sometimes for no apparent reason the burner will burn for 30 secs to 2 minutes, then shut off. Then the next cycle the burner will only light again for the 3 to 5 seconds

I'm guessing the coils are bad, but just wanted to see what other think.

Thanks for you input