Our Goodman GMP075-3 furnace was coming on and only staying on for 10 sec. then shutting off. I removed and cleaned the Flame Sensor (Thanks for the tip) and now that I have reinstalled the Sensor the Igniter will not come on when the unit calls for heat. I do smell gas (so the valve is opening) but will not ignite. How do I check or fix the igniter?

The ignitor is usually held in place with 1 or 2 screws. Turn off the power, unplug the ignitor wires, carefully remove the ignitor & inspect for burnt spot (usually white or light gray) or hairline crack.

I located it to the right of the sensor, I removed it and cleaned it. Still will not light. May have to call tech tomorrow.

Does the ignitor glow during the ignition process? If not & you have a volt meter, check for 120 volts AC between the ignitor terminals during the trial for igntion period.