I replaced the fuel pump last summer after series of low idling and stalls. Fast forward to last week, after two days of rough idles, car dies with no computer codes. After twelve hours rest, it will start and run for one minute before dying. After two days of resting, I get four codes p0300, p0302, p0303, p0304, all cylinder misfires. This is a recurring problem with my car, but once I replace an ignition coil, all appears well again.
So I replaced second coil today and all the spark plugs. Computer codes disappear and the car starts, but now dies after ten seconds. My best guess is some electrical issue caused the cylinder misfires and fuel system issue. I've solved the cylinders, but don't know what to do about fuel system since I just replaced the pump last summer. I can check fuses next, but what's next? IAC valve? Pressure test the fuel line? Any thoughts? Mechanic told me a full electrical diagnostic would cost more than the car is worth, so I'm ok with solving the symptoms for now but not knowing the underlying cause.