ok got my newest crx and it has a fuel cell.it was running fine but then started acting like it could only use part of the gas in the cell!?!?...i dont get it??it will stutter then cut out or idel really low (700-800)but if i fill it back to the top its fine,but after a third of the gas is gone it acts again.does any one know what this might be?ive never had a fuel cell in one of my cars so im lost

.....thanks for any help,mike