I have a 1992 Ford Mustang 5.0 five speed with intermittent starting issues. When I turn the car on I hear the fuel pump prime like normal, but then it won't shut off. other times it does not turn on at all. Once in a while the fuel pump will run for three seconds and shut off like normal and the car will start right up and run smooth. when I shut the car off and back on, the pump won't prime, and the car won't start. I have checked the inertia switch, I have hot spark, good fuel pressure, new fuel filter, and power to the injectors. I have tried to get the codes, but most of the time i can't get them to flash. I did get one reading while the car was running Codes:91,21,41,77, and 67. The fuel pump was getting 7v when i checked it, kind of a funny number i thought. I think it might be the engines computer, but this is because i can't think of anything else. anybody have any ideas????????????? Any way to check to check the computer???