Testing a gas oven with a simple multimeter will aid in a proper diagnosis. If your glow bar is glowing red and no gas makes it down the flue it can still be bad.
Using an amp clamp you can verify a ignitors proper operation. In this explanation I’m referring to the flat style ignitor, more commonly used in the appliance industry.
The ignitor need’s to draw 3.2 amps to open the gas safety valve, when the ignitor reaches the correct amps the valve opens and the gas will light. Over time an ignitor will get weak or just break, replacing the oven ignitor is an easy feat with the correct tools.
Remove bottom of the inside of the oven, this will lead you to the igntor. Once the panel and shields are out of the way you will see the ignitor on the burner tube.
Tip here is when removing the screws from the burner base add a drop of oil, doing so will aid in the ignitor screws removal. With the ignitor off the tube you will have to disconnect the wires, if there is not a harness you will need to cut and splice the new oven ignitor into place.
Using only ceramic wire nut is recommended they hold up to heat better then plastic. Once the oven ignitor is in place assembly the unit and test for proper operation.