Recently our car decided to start missing. It got worse over a couple of days and finally quit. We replaced the plugs, plug wires, coil, and coil harness. The car was (still is) running great, and the check engine light had gone out. But then it came back on after driving a few miles down the road. We disconnected the battery to reset it, but then it just comes back on after you drive a little while. There is nothing wrong with the car as far as we can tell now. Any idea why the light would stay on?