I was driving my daughter to my moms one November morning and in a 10 mile ride my car spit and sputtered and shut off. After it sat for a few mins I was able to crack it and go on but within them 10 miles my car did this 3 times. I was told by my brother in law who lives out of state, that it sounded like my fuel pump so I replace it. Now my car runs rough like it is only hitting on a few cylinders. What could be wrong now? The engine was not running like this before the fuel pump change.