Hi, my sister bought an 04 Sante Fe 4 cylinder and after driving it for a say an hour, its starts missing and the check engine light flashes on and off. One shop found misfire codes for 1 and 4 and replaced the coils and all plugs/wires and it still did it. While traveling it started so she stopped at a diffrent shop that said the fuel pump was going out and they replaced it. They said it showed random misfire code. She said that made the car feel stronger but shes still getting a miss at highway speeds. I told her to clean the MAF sensor and to stop at Auto Zone or something to get the codes read, shes doing that today. Is there anything common with these cars that causes this? I believe it has alittle over 100,000 miles.