I have a 4.3 LTR OMC Cobra GM motor. The motor will start and die immediately. I first thought it might be a fuel problem. I have change both fuel filters. Points, Condensor, Spark Plugs. I am getting fire at the plugs but not for a few seconds. I have also checked the ignition switch and it appears to be working fine. I was wondering about checking the coil to see if it is working properly. It appears that I have fire when the starter is engaged but not when I turn the key back to run. 
