Help ignition problems at Jetta A4

Hello, how do I have a A4 mod 99 jetta one day I had been driving when suddenly the car lost power the coil stopped sending spark to the spark plug 2 and 3 Well, as I could come home, trying to find the fault I did tests to the sensors of the smelly tree oxygen and air. Cause request help from colleagues we scan and do not send codes because it turns out that two months ago the car stopped sending spark to all the spark plugs now or starts to change the ECU was encoded and everything because the blessed car does not turn on no longer change the air flow sensors.