I have a Rheem Criterion RCBA-2457GG17 Furnace and it shuts on and off at random. The meter/thermostat seems to work fine, I changed the filter, and when it does turn on again the gas ignites for a brief second but then the igniter light and gas shuts off.

Sounds like the flame rod needs cleaned.

http://www.mobilehomerepair.com/media/img/coleman/025-30788-700.jpg

Thanks for the reply and pic, I'll give that a try

Just rub it with some sand paper or steel wool

It will be on the opsite side from the ignitor