Furnace Burners won't ignite

[Need Advice]

I have a Rheem Criterion Furnace, Model RGDG-10EAMER that has been giving me problems lately.
The burners will not always light. The igniter comes on and glows red hot, I can hear the sensor trip the value to release the gas to ignite, but there is not ignition of the burners. It will cycle and the blower will start but still the burners will not start. I have cleand the furnace checked the wiring and the IIBC board, the green light comes on to show there is power to the board. After tinkering with it for a while and vaccumming out the furnance and have turned off the gas and the value and the power swith to the furance and then turning it all back on it will light ( I think it has more to do with the time lapse of having everything tunred off and not any I really did), but it will run for the day and cycle several times throughout the day, but it eventually stop again and I go through the same process again and it will ignite again, but of course it will stop again until I go through the same steps. Any ideas of what is causing the problem?

[AmeriServ]

Sounds like you may have a gas valve problem. The operation is fairly simple as you seem to already know,
1. call for heat 24 volts from T-stat
2. inducer motor starts and is proved through a pressure switch
3. Igniter heats up
4. Gas Valve Opens and Flame is proved by flame sensor
6 Blower starts

The following general things can shut it down
Loss of pressure from inducer fan
Loss of or No Proved Flame
Flame Roll Out (flame blowing backwards essentially)
High Temperature in heat exchanger box

You can sometimes still hear the click of the gas valve when they are stuck closed by debris or other failure.

[mike n]

Stop guessing do not turn the power off and on when the furnace fails it will give you a failure code in the form of flashing lights from the control board get that code and then tell us what it is