During the code test we got code 13. The idle is between 800-1000 and sometimes 1200. I had a couple of days of dying within a mile of the house when I was stopping at a light. Now it isn't dying but it is surging from 400-1500 rpm while driving. It has been tuned up, checked timing, cleaned IAC, vacuum gauge test was fine (not the hand held one checking every line). Any ideas would be greatly appreciated. The hubby is not real interested in finding out the problem but I am because it is an awfully heavy vehicle for a couple of girls to push if it wont start.