2001 CRV CEL flashing with no codes

I have a 01 crv 4wd EX with a CEL that flashing with no codes i did a tune up adjusted the valves to exact specs.... checked timming changed the plugs wires cap and rotor (all with honda factory parts) and still get a flashing mil... i have a snapon MT2500 and everyonce in a while i get P0304 (miss on #4) but when i cycle the ignition it goes away and then after running for about 20sec it starts flashing the CEL but no codes will be present! my trouble shooter says that if the code doesnt come back ... the ECU has failed can anyone shed some light or have any other ideas???

i unhooked the battery for 1min and test drove it and it went away runs like a screaming ape

I usually find that unhooking the battery helps a lot of small issues I cannot seem to answer.

Easy fix by the sounds of it. :cool: