I have a Whirlpool wfg510s0ab2 oven. During normal operation, it sparks 3 times (it uses spark ignition NOT glow) and then about a minute later sparks once and lights. A few weeks ago it started sparking 3 times the second (and third and forth etc.) and didn't light about 20% of the time. Now it is not lighting 80% of the time.
I visually verified that both the broiler and oven sparker are sparking. When the oven is working both broil and bake work and when it isn't working neither will light.
Test mode shows good.
from my research online it seems it can be the ignitor, gas safety valve, or the spark module.
It seems unlikely to be the ignitors since they both work occasionally and they both still spark when the oven works.
The spark module looks okay, there is no obvious swelling or discoloration.
Is it definitely one of those things? Is there a way to test to verify?