1998 Saturn SL2 Gas tank filling problem

Problem filling gas tank. Initially started by not accepting fuel on faster gas pump nozzel setttings. It would always stop fuel delivery due to gas bubbling up into nozzel. Then it started doing this on the first, slower gas nozzel setting. Now it only will allow filling while holding the nozzel at the very slowest delivery rate. "Seems" to allow an amount of gas equal to what would fill the tank filler tube, then burps out some air (spectulating), then fills tube again-burps, and this cycle repeats.