Coleman Evcon furnace help

Hey guys, first of thanks for taking a look at my problem I am pretty confused by it. I have a Coleman Evcon furnace that lights up fine and will run for several mins. Then it will shut down and try to relight three time then give me an error flash code of 7 which is the code for locked out due to no ignition. I have no idea what is causing it. I have watched it run its course several times there is nothing my untrained eyes noticed as odd. I did take the flame sensor out and cleaned it with some steel wool to no avail. I am all out of ideas any help or feedback would be greatly appreciated.

 

Either the heat exchanger is cracked and blowing the flame off the flame sensor, or a failed flame sensor (doubtful), or a failed control board. Do you have a meter that can check DC micro amps (uA)?