I have read many different threads regarding similar situations with these furnaces but mine seems a bit different. i have the kg6ra 096c-12b model and when heat is called for the furnace begins its normal process - the ignitor glows, gas valve opens and i get full flame across all burners, BUT within 2-3 seconds the flame is gone [im assuming the gas valve closes]. my first instinct was the flame sensor, which appeared fine but i cleaned it up anyway and tried again. i even replaced it with a new 1 thinking that was sure to be the problem, still no luck. its always the same situation, everything appears to be fine but i lose the flame within seconds. after it tries to reignite a few times i get the error code of 4 flashes meaning ignition failure [check ground], which is what most people seem to get when they have no ignition at all. a friend of mine owns a heating/cooling business and since this is his very busy time of the year and he knows i can handle most repairs on my own he told me i should replace the ignition module because he believes that to be the issue. i am in no way doubting him, but at the same time he is basically giving me that advice based on the same information i am supplying here, so i was wondering if anyone else had an opinion or better yet had the same experience and what their fix was. if the ignition module cost the same as a common sensor i would have bought it already, but i figured i would get a second opinion, any ideas? thanks in advance

I have a goodman HVAC system model number GMNT080-4B and it won't heat. Opened the upper portion and the propane is getting lit by the lighter and runs for about 5 seconds. Then shuts off and goes through the cycle again and again until I turn the system off. Opened the bottom and the circuit board (white rodgers 50T35-730) has solid light which from my web searches is a good thing. Fan works when system set to fan on. Any ideas what else to check?